BBW mother discovers a secret...

Alison Gilbert covered her mouth with her hand to stifle the gasp that nearly escaped. The 45 year old mother of three was standing outside the bedroom door of her 19 year old son, Jason, unable to fully process what she was seeing through the thin crack between the door and its frame. There, laying on his bed, was Jason. But he was not alone. He was laying on his back naked, and straddling him equally naked was his 25 year old sister Sarah.

Just minutes ago Alison had been working out in the family home's basement as she did for 2 hours every day. After only an hour today, however, her AirPods had died and she had made her way back upstairs to charge them, vowing to continue the second half of her workout once they were fully charged. To her surprise as she approached her son's bedroom door she had heard moaning, and seeing that his door was open a crack she could not resist peaking. The moans had been unmistakably female, and she was curious if Jason had a girlfriend that he was hiding from the family.

She had definitely not been expecting to see her eldest daughter slamming her voluptuous ass down on her only brother's sizeable cock. Sarah was riding Jason like a woman possessed, her back to the door and her generous curves rippling with the force of their fucking. Although she couldn't see from this angle, Alison assumed that Jason's hands, and maybe his mouth, were full of Sarah's enormous tits. The mother could feel her pussy moistening at the sight of her two eldest ******** committing i*****. Her mind was a whirlwind of contradictions. Her logical brain knew she should walk in and stop them. But the rest of her brain was experiencing two very strong emotions that kept her frozen in place. One was horniness, horniness like she had never felt in her life. The other was fear, fear of what she might do if she crossed the threshold into her son's room.

Despite herself, Alison found her hands wandering over her own generous curves as she watched the siblings fucking. She began rubbing and pulling on her nipples through the thin sports bra she wore during her daily workout sessions in the basement. She was about to stick her hand down her leggings and rub her throbbing clit when she heard Jason moan much louder than he had been, and Sarah said something that made her mother freeze in place.

"That's it baby, cum for mommy. Cum deep in mommy's pussy."

Alison could see her son's cock throbbing in his sister's pussy as she said those words, could nearly follow the journey of his load as it sped from his swollen balls up the impressive length of his shaft and deep into the eager womb awaiting it. She had to bite her lip to keep herself from moaning out loud as the combinations of her hands pinching her hard nipples and the forbidden sight in front of her brought her to orgasm. She felt her own juices soaking the front of her leggings, all without laying a hand on her long neglected pussy. Coming to her senses, she looked into the room again to see Sarah and Jason making out furiously, caught up in the post-orgasm passion of their ********* fucking. Alison crept away from the door, back down to the basement as quietly as she could before either of the siblings realised that had been watched.

Down in the basement the flushed and horny mother gazed at herself in the large mirror covering one of the walls. Alison was what some would call a BBW. Some might even go so far as to call her an SSBBW. Her long flaming red hair framed a round face that looked much younger than her 45 years. At 5'4" and 250lbs, her huge belly, massive thighs and gigantic ass were only overshadowed by her impressive 46P bra size. No matter how much she worked out, however, she was never able to shift any of the weight. Her workout sessions had begun five years ago, after her divorce from her husband Keith. She had always been an extremely big girl, and Keith had worshipped her curves from the moment they met in college, so her size hadn't been a factor in the divorce. In fact, the two had parted ways quite amicably, both of them realising that although they cared deeply for each other they no longer made each other happy as partners. Keith's booming architecture business meant that Alison had never had to work since she graduated with her degree in Literature Studies, and even after the divorce he happily continued to provide for her and their three ********.

******** who were now fucking each other, or at least two of them were. An image of her younger daughter, 18 year old Sophie, gagging on her brother's huge cock flashed through Alison's mind and her nipples were suddenly rock hard again. She studied her body in the mirror more, noticing all the similarities between herself and Sarah. The two of them had been mistaken for sisters before. Sarah had seemed to take the entirety of her genetic makeup from her mother. Same height, same flaming red hair, same piercing blue eyes, same soft pale skin and same BBW body. The only difference between the two was that without the effects of age and childbearing, Sarah had not yet reached her mother's size. Everything was just a little bit smaller on the 25 year old. Belly, thighs, ass and boobs. Having taken her daughter shopping on more than one occasion, Alison knew her bra size was a 40KK.

Sophie had also inherited some of her mother's features. Her blue eyes and pale skin were where their similarities ended, however. Sophie was a petite 4'7" and seemed unlikely to get a late growth spurt. Her hair was an almost white blonde that neither her mother or father could figure out the origin of, since Alison's parents were also both redheads and Keith's entire family sported jet-black hair. Sophie was also extremely slim. She seemed to have the opposite problem to her mother and sister, eating like a plague of locusts without putting on a pound while they looked at a salad and gained ten. At only 80lbs, she had a small rounded butt and wore a 32A bra.

Jason had inherited the most from his father out of the three siblings. Black hair and deep brown eyes. The young man had actually surpassed his father's 6'1" by the time he was 15, and by 18 he had reached his current 6'4". Despite having no interest in sports, Jason had maintained an impressive physique through daily gym and swim sessions since hitting 16, and had maintained the routine in his first year of college. Remembering the scene from the bedroom earlier, Alison thought to herself that bulging biceps and washboard abs weren't the only impressive parts of her son's body. The horny mother hadn't been able to tell how much of Jason's cock had been buried in his sister's gushing pussy, but it had definitely looked to be longer and thicker than his father's admirable 8 inch tool.

As she thought back on the sibling fuckfest she had just witnessed, Alison couldn't help but notice the similarities to herself and her ex-husband. Jason was the spitting image of his father, and Sarah was the twin of her mother. Watching them fuck was like watching an old recording of herself with Keith back in their college days. He had always loved it when she got on top of him, bouncing on his hard cock while he filled his hands with the supple flesh of her belly and tits. She had always cum so hard when he started sucking on her nipples as she rode him, feeling his hands ******* every inch of her belly like he would never be able to touch it again. No man had touched her like that since the divorce. In fact, no man had touched her in four years. She had tried online dating a few months after the divorce was finalised and had a couple of hookups before realising that while plenty of men wanted to fuck her, none of them wanted to be seen in public with her. Conversations on the apps inevitably led to invitations to guy's houses late at night. When she got tired of meaningless sex she had started countering with an offer to meet for coffee the following day, only to find herself unmatched shortly thereafter. The experience had made her swear off dating at all, throwing herself into raising the kids and resigning herself to the use of fingers and toys to get herself off.

She needed a real cock though. She needed to feel a man throb as he bust his load deep inside her. Toys couldn't fulfil that need. Not like Jason had fulfilled that need for Sarah. And had she said to him that pushed him over the edge? 'Cum for mommy', wasn't it? Alison sat down on one of the nearby yoga mats and quickly pulled her leggings to her ankles. The smell of her aroused and dripping womanhood assailed her nostrils, and she pulled off her sports bra and began pinching and twisting her nipples with her left hand. Her right hand made its way to her needy pussy, vigorously rubbing at her throbbing clit. She was picturing Jason fucking Sarah, but then it changed. She was watching herself in Sarah's place, impaling herself on her only son's manhood, begging him to flood his mommy's desperate womb with his seed. Knowing the basement was soundproof, she let loose with her moans and groans and dirty talk as she touched herself.

"That's it Jason, fuck mommy! Mommy needs this so bad baby! Plough mommy's cunt with that massive cock and make me my son's i***** whore!"

She came as Jason came in her fantasy, the imaginary cum filling her with warmth as her pussy spasmed and gushed. For a few minutes she was in bliss, cumming harder than she had in years, even harder than she had outside Jason's room earlier. When she recovered, she saw that her leggings, thighs and hand, as well as the yoga mat beneath her, were completely soaked in her juices. Luckily the basement home-gym had a built in shower, and Alison always kept a change of clothes down there for after her workouts. After washing herself and changing, she made her way back upstairs and almost walked head first into Jason.

"Woah there mom! I was just coming to check on you, you've been working out a lot longer than usual."

She looked her son up and down. He was the same young man he had always been, same kind and gentle smile looking down on her as always. There was nothing about him that gave any indication that he had just creampied his older sister.

How long has this been going on? She wondered.

"Sorry honey," she said, trying to compose herself. "I got a bit distracted. I was 'In the Zone', as you kids say. What do you feel like for dinner? I'm not in the mood to cook and we all deserve a little treat, don't you think?"

"Definitely mom." Jason replied, "How about Indian? I know Sarah hasn't had a chance to try that new place in town since we got back from college."

Jason had just finished his first year of a Literature Studies degree, while Sarah was heading into her final year of Law School. They were both based in the same college, which was also where Sophie was planning to go to study architecture now that she had graduated High School.

Has he always been so concerned about what Sarah wants? Alison wondered.

"That sounds great sweetheart." she said.

"Thanks mom, you're the best." he said, stepping in closer and wrapping his powerful arms around her. She felt her nipples hardening again, unable to keep the image of his cock pumping in and out of his sister out of her mind. When he leaned in and gave her a kiss on the cheek, an innocent gesture that he had done for nearly 20 years now, she felt ashamed at the renewed flood of moisture between her legs.

Later that evening, the family was sitting down in front of the television eating their Indian food. Sarah and Jason had taken one end of the couch, sitting closer than brothers and sisters would normally sit given the length of the couch. Sophie was tucked into the corner of the other end, her legs crossed beneath her and her eyes and thumbs glued to her phone. Alison was sitting nearby in a reclining armchair, a plan forming in her head. She grabbed the remote and paused the movie they were watching.

"Sarah sweetie," she said, catching the slight jump from both her older ********, "how about the two of us go for a spa day tomorrow? They just finished renovating the sauna area and I really want to try it out."

Before Sarah could respond Sophie looked up from her phone.

"Thanks for inviting me mom." she said, rolling her eyes.

"Well dear, you're welcome to come if you want. I was thinking your brother might be willing to take you to that new movie you've been dying to see though, the one about the zombies?"

"Love in Vein 5? It's about vampires mom, not zombies." came the sassy reply.

Despite the response, Alison knew her youngest ***** would take the bait. Sophie was obsessed with all things goth, and had been begging to go and see the R-rated fifth instalment of the vampire romance series since the first trailer dropped a year ago. Keith would have a heart attack if he found out, but Sophie was 18 now and Alison figured adults can make their own decisions about the movies they watch. More importantly, it would keep Jason and Sophie busy while she brought Sarah somewhere private for a talk about what was going on in their home.

"You don't mind bringing her, do you Jason? It would mean so much to mommy."

For a second Alison thought she might have pushed it too far. She hadn't referred to herself as mommy since Sophie was 12 and the name was deemed childish. She saw Jason gulp, and a flash of amusement in Sarah's eyes.

"Sure thing mom, I'm happy to bring Elf to the zombie movie."

On hearing her brother's childhood nickname for her, Sophie throws a cushion at his head. The undercurrent of tension in the room was broken and they all laughed as the plan fell into place. Alison wondered how she would confront her eldest daughter the next day. More importantly, she wondered why she wanted to confront her. Was she upset? Concerned? Jealous? Maybe a little bit of all of them. After everyone went to bed Alison made her way back down to the basement, bringing herself to several loud messy orgasms thinking about her son and how it would feel to be a slave to his cock.

*

The next day Alison and Sarah made their way to the spa to try out the new saunas. Alison had made sure to book one of the smaller sauna rooms for herself and her daughter, one where they would not be disturbed by fellow spa goers. As they sat down in nothing but their towels, she once again thought about how similar the two of them looked. In another 20 years, after Sarah had popped out a kid or two, they might even look identical. She made a mental note to bring up birth control with her daughter at some point during their conversation. She and Keith had started Sarah on the pill when she was 15, more to regulate her period than anything, but Alison had no idea if she had continued taking it into her college years. And there had certainly been no condom covering Jason's weapon yesterday as he unloaded into his sister.

"I really needed this, thanks mom." said Sarah.

"Well actually honey, there's a reason I invited you to come along. There's something I need to talk to you about."

She could see Sarah sitting up straighter through the steam at these words.

"First off, I want you to know that as your mother I love you unconditionally. No matter what you do, or what happens, that will never change. You will always be my firstborn ***** and I am so proud of everything you've accomplished so far."

"Mom that's so-"

"Now, having got that out of the way I'm just going to come out and say it. I saw you and Jason yesterday. I saw the two of you having sex in his bedroom."

Sarah's pale skin had been flushed from the heat in the sauna, but Alison watched as the colour drained from her face. She just stared, horrified, at her mother without speaking.

"Like I just said, I love you unconditionally and that will never change. I'm not angry or disappointed or anything like that, I'm just so confused. I want to know how this happened. You're a beautiful young woman, and Jason is a handsome young man, I'm sure neither of you were lacking in willing partners in college. So why?"

Sarah was silent for another moment, and then she started crying.

"I'm so sorry mom, we never meant for this to happen!"

"It's ok sweetie, it's ok." Alison replied, scooting over to hug her daughter. "I just want to know how this all happened."

Stifling her tears, Sarah recounted the events that had led to her ********* coupling with her younger brother. For years she had been going out with Ethan, another law student. He was hot, smart, and kind. The whole package. He also had a plan in life. Sure, it amounted to being handed a job at his father's law firm the second he graduated but it was a plan nonetheless, which was more than most college boys had. The two of them had discussed marriage, ********, where they would buy their first holiday home, the works. And it didn't hurt that Ethan was good in bed. Even after years together they still fucked like rabbits at every opportunity.

Then, at the beginning of the last semester, Ethan had broken up with her. It had come completely out of the blue, no warning. One minute they were Mr. and Mrs. Ethan Singer and the next minute he wouldn't even look at her. It took two weeks before Ethan's best friend Sam took pity on her and told her the truth. Over the Christmas break Ethan's father had pulled him aside and explained to him that his future at the firm, as the son of a name partner, required more than just brains. It was also about appearances. Ethan's father had apparently told his son "I like Sarah, she's got brains to burn and she's going to be a damn good lawyer. But if you want to impress the partners and the clients, the girl on your arm has got to be more... traditionally beautiful, understand?". The exchange had prompted an argument that only ended when Ethan was given an ultimatum; dump the fatty, or dump the family. So he broke up with her, and according to social media he was already dating a tall, skinny, blonde psychology major.

Hearing all this, and seeing Instagram photos of that stick insect hanging off of her man, turned Sarah's heartbreak into rage, and that was when Sam made his move. He told her how beautiful she was, how Ethan was an idiot and how he'd always had a crush on her ever since she started dating his best friend. So she left him fuck her. Like most men he went straight for her tits, sucking on them the minute she pulled them out and leaving her to undo his trousers and **** his cock out. Regret set in the minute Sarah felt it, rock hard and still not pushing past four inches. Unwilling to let go of this chance to hurt Ethan though, she lay back and hiked up her skirt, pulling down her panties and guiding Sam's cock into her. He lasted about two minutes before he groaned around her nipple and collapsed. The brief encounter had satisfied Sarah's craving for revenge, but it had awoken a much more desperate craving deep inside her, a craving that had been hibernating for two weeks. After years of multiple orgasms nearly every day with Ethan, two weeks of abstinence followed by two minutes of bad sex had now left her with a burning need to be fucked until she came hard. To that end she went to her favourite bar near the college campus, and that's where she met Jason.

"You're brother's not old enough to drink!" Alison interrupted her daughter's story, somehow more shocked at the idea of Jason going to bars than she had been at the sight of him fucking his sister.

"That's what fake IDs are for, mom." Sarah explained, before continuing to tell her tale.

Jason had spotted his older sister sitting alone at the bar as he came in with his friends. He immediately went over to check on her, finding her several whiskey's deep and very unhappy. So he sat down and ordered himself a drink and tried to cheer his sister up. Sarah, for her part, appreciated what her brother was trying to do. But him sitting beside her at the bar made it a lot less likely that any guys would approach her and hit on her. Not that it had been happening at all prior to Jason's arrival. Eventually she began to relax, and forget about Ethan and Sam and all the misery of the last few weeks. The two of them joked around like they had when they were kids, except now with added alcohol. Just as Sarah seemed to have perked up back to her usual cheery self, one of the girls from Jason's group of friends made her way over to the bar. She tapped Jason on the shoulder and asked him "Why are you sitting here hitting on this whale when you know I'll spread my legs for that massive cock anytime you want?"

Sarah had never seen her brother so angry in all 19 years of his life. She was used to the comments about her size, but it was something Jason had never tolerated. More than a few boys in school had been beaten up for mentioning weight and Jason's family in the same sentence. Sarah didn't really think that Jason would hit a girl, even if she was a bitch, but he would definitely make a scene over the comment and that was the last thing Sarah wanted happening in her favourite bar. She hopped off her bar stool, grabbed her coat, purse and brother, and dragged him from the building in silence. Neither of them had been in the mood to go to another bar, so they had gone back to Sarah's studio apartment and cracked open a few more beers.

"Look, I'm sorry about Giselle." Jason had said after a while.

"Is she your girlfriend?" Sarah had teased.

"No," he laughed, taking another sip of beer, "we've just been hooking up a bit but she's been getting really clingy lately. That's not the first time she's interrupted me with another girl but she's never been that horrible to anyone before."

"Well it definitely seems like she wants to be your girlfriend." Sarah teased some more. "Or at the very least she doesn't want anyone else getting their hands on your 'massive cock'."

The sibling had laughed then, Jason out of awkwardness that someone had told his sister he was well endowed and Sarah at how awkward the whole exchange had made her brother.

"Well she won't be getting her hands on it again after that." he laughed. "Nobody talks to my sister like that and gets away with it."

"You know we never explained to her that I'm your sister," said Sarah, still laughing, "she probably thinks you're fucking me right now."

The mood changed in the room at that point. Sarah had been thinking about Sam and his unsatisfying attempt to please her. She wondered just how big a cock had to be to be described as 'massive', and if a cock like that could have kept her from going out looking for a hookup that night. She involuntarily glanced down at Jason's crotch and saw that a bulge was beginning to develop. It already looked like it would dwarf Sam's pecker, and even the memory of Ethan's pussy pleaser was seeming small in comparison. She had looked back up into Jason's face and found that he had caught her looking at his crotch. They stared into each other's eyes for what seemed like hours, although it could only have been a few seconds. Then, spurred on by horniness and alcohol, they lunged at each other.

Their mouths mashed together in frantic passion as they began ripping each other's clothes off. Sarah's pussy began gushing as her hands roamed over her brother's toned muscles. Unlike every other guy she had ever been with, Jason only briefly groped her huge tits. His hands quickly moved south to her belly, feeling every inch of the soft flesh, his moans growing louder as he jiggled her rolls. The attention to her belly, the part of her body she was most insecure about, drove Sarah wild. The moment Jason's cock was free of his pants and boxers she pushed him back on the couch. Pulling up her skirt and slipping her panties to the side, she mounted him and in one swift movement impaled herself on her brother's huge cock. They fucked hard and fast, Jason still trying to touch every bit of his sister's body like she was the only women he had seen in years. She held his head between her tits as she came, her pussy clamping down on his tool like a velvet vice and milking the cum from his balls. After cumming simultaneously, they passed out right there on the couch, still tangled together in a sweaty cum-soaked mess.

"So that's how we fucked for the first time." Sarah told her mother. "The next morning I freaked out and started crying. The love of my life had left me and now I'd ruined my relationship with my brother. All I'd have to do was fuck dad and I'd have the trifecta of messing up all the important male relationships in my life. But Jason just held me and told me he loved me. He said that he'd been dreaming about this since he hit puberty and if I never wanted to do it again that was fine but he'd always love me as a brother. After I calmed down we had a proper talk and we figured if we both wanted it why shouldn't we keep doing it? Jason has been sleeping with some other girls just to keep his friends from getting suspicious, but I haven't fucked anyone else since that night. If people ask, I tell them I'm not ready after Ethan. That shuts them up pretty quick."

Alison didn't know what to feel. Part of her, the part conditioned by societal norms, wanted to tell Sarah that the relationship with her brother had to stop. On the other hand, mer maternal instincts wanted her ******** to be happy, and if happiness came from fucking each other so be it. She was also proud of her son. He really had grown into such a fine young man, taking care of his heartbroken sister. So what if the way he went about it was a bit unconventional? More than anything though, Alison was horny. The heat of the sauna was nothing compared to the heat in her pussy as she listened to her daughter describe the i*****ous tryst. That was the part of her brain that spurred her next question.

"Sarah, when I saw you and Jason yesterday I also heard some things. I...I... I heard you call yourself mommy..."

Sarah looked closer at her mother then. It dawned on her that the flush in her face wasn't just from the steam, and the damp on her inner thighs wasn't just sweat. The older woman's nipples were hard enough to show through the towel, and her thighs kept rubbing together in a way that Sarah recognised as desperation to get off.

"That started about a week before we came home for the summer. Jason was pounding me doggystyle, pulling my hair and spanking my ass. Then he grabbed my hips and really started going for it. It think it was the hardest he'd ever fucked me up to that point. And then, as he was cumming, he moaned out 'fuck mommy!'. It was a little bit awkward after he recovered and realised what he said, but I was kinda into it so I started using it. I didn't think the sex could get any better but I was wrong. But why are you asking about that mom?"

"Well, I...I-"

"You know, I think half the reason Jason always wanted to fuck me is because I look like you." Sarah continued. "I think when he was pounding me from behind he was imagining it was you on your hands and knees in front of him, taking every inch if his big fat cock in the pussy that he came out of"

Sarah moved slipped her hand under her mother's towel and found the sopping mess of her pussy. Alison moaned as she felt her daughter's finger enter her, too horny to stop her.

"You didn't want to talk to me about this because you're concerned. You wanted to talk about it because you want to fuck Jason too!"

"No, I... I'm his mother!" Alison tried to protest.

"And I'm his big sister who looks just like our mother and calls herself mommy while she's fucking his huge cock. He might not have ever said it out loud, but I think we all know he wants to fuck you. Your baby boy wants to slide every inch of his massive tool into your cunt, mom. Do you want to know how big he is?"

"I...I..." Alison couldn't speak properly. Not only had Sarah added a second finger to her mother's dripping hole, but the young woman had manoeuvred her thumb over Alison's throbbing clit and with her free hand had pulled the towel off her mother's tits and begun assaulting her hard nipples.

"I need you to say it, mom." Sarah whispered in her mother's ear.

"Yes! Fuck yes! I want to fuck my baby boy! I want him to fill me with cum every day! Please tell me how big my son's cock is baby! Please tell me and make mommy cum!"

"He's 10.5 inches." Sarah replied before dipping her head down to take one of her mother's nipples in her mouth.

Alison didn't last long. Both of her nipples were being played with, her daughter's tongue lashing across her right nipple while Sarah's fingers pinched and twisted her left nipple. The towel fell away from her body, revealing Alison's legs spread as wide as they would go and Sarah's hand furiously working on the dripping pussy between them. The combination of the taboo coupling she was experiencing with her daughter, and the confirmation that her son not only had the biggest cock she'd ever come across but wanted to use that cock on her, his mother, made Alison cum like a freight train. Sarah took her hand away from her mother's nipple to cover the older woman's mouth as she moaned through her orgasm. This wasn't a scene they wanted a concerned spa attendant to walk in on. Once Alison had managed to catch her breath, the two women began to formulate a plan for how to get Jason and his mother into bed together.

*

Across town, while Alison and Sarah were having their 'talk', Jason and Sophie were sitting down in a movie theatre watching Love in Vein 5. Jason found the entire series ridiculous. All of the movies centred around the trials and tribulations of navigating romances in a world filled with vampires, werewolves, ghosts, goblins, witches and warlocks. Love in Vein 5 was the studio's attempt to revamp, no pun intended, the series after abysmal returns at the box office for the fourth instalment. Up to now they had all been fairly PG, the sex was all implied and the most risque scenes consisting of intense make-out sessions. The new movie had gotten an R rating, and with good reason. The director had apparently said in an interview that the mistake they made with Love in Vein 4 was not acknowledging that their audience was growing up and were ready for more mature content, a mistake they would not repeat this time.

In the scene they were watching right now, a warlock had cast a spell to allow a ghost, the love interest of the vampiric main character, to have a solid form for just 24 hours. The vampire was slowly undressing herself, getting her partner ready to finally consummate their relationship. Despite himself, the striptease was getting Jason horny. The actress playing the vampire was a sexy redhead with pale skin just like his mother and older sister. She wasn't a big girl by any stretch of the imagination, but she did have big tits and a juicy ass. She would have been enough to get any young man's blood flowing just by herself, but her hair and complexion and big tits made Jason think of Sarah and the intense sex that had been having the previous day. Having sex with his sister really made him appreciate that the fact that his mother's home gym in the basement was soundproof and she was a stickler for routine. The second she went down for her workout the siblings knew they had exactly 2 hours to enjoy themselves before she came back up. That just meant hopefully getting the timing right between their mother's workout and Sophie's visits to her friends houses.

Jason's head was so full of fantasies about his older sister that he never noticed his younger sister reaching for the bag of popcorn in his lap. In the darkness, her hand missed the bag and travelled downwards until it came to rest on his engorged member. Both siblings froze, only a thin layer of denim separating Sophie's petite fingers from her brother's swollen cock. They seemed to stay like that forever, until someone in the theatre coughed and broke the spell. Sophie quickly pulled her hand away.

"Sorry." Jason whispered over to his sister.

"It's my fault," she whispered back. "I should've checked where the popcorn was before I started ******* around in your lap."

The two of them watched the rest of the movie in silence. When it was over, they quickly left the theatre and started heading back to Jason's car. As they reached the car Sophie stopped, her phone in her hand.

"Hey I just got a text from the twins asking if I want to go hang out. They don't live too far from here so I'll just walk over instead of making you drive me like a chauffeur."

"If you're sure." Jason shrugged. "Just don't be too late home, you know how worried mom can get."

"Alright dad!" Sophie laughed, then turned and skipped out of the car park and down the street.

Jason sat into his car and sighed. Sophie had seemed fine about the whole thing in the theatre, so hopefully she didn't think he was some kind of pervert getting hard next to his sister. Speaking of getting hard next to his sister, there was a good chance his mother might still do her daily workout in the basement after the girl's spa day. With Sophie out of the house it was the perfect opportunity to enjoy some alone time with Sarah. The last time they had gotten to do it two days in a row they were back in college, and the thought of his sister's curves made the blood rush down to his cock once again.

*

"I swear to God guys, it was fucking huge!"

Sophie was laying on her best friend Melanie's bed, recounting what had happened in the theatre. Sitting on his own bed was Melanie's twin brother Marcus, who asked;

"Ok, but how was the movie?"

The Cho twins were just as goth as Sophie herself. Half-Asian and half-white, Melanie was closer to Sophie's height at 4'10" while Marcus was taller again at 5'1". There was a much larger difference in the twin's height right at that moment, however, as Melanie was on her knees between her brother's legs inhaling his 7 inch cock.

"I couldn't even pay attention to the rest of the movie after that, all I could think about was how big he felt." Sophie replied, unperturbed by the i***** happening just a few feet away from her. It was the Cho twins who had awakened Sophie's own ********** desires for her brother when they confided in her that they had begun fucking the day they turned 18 just about six months ago. They had waited until Sophie herself turned 18 last month to tell her, but Sophie had always had an inkling that the twins were closer than normal brothers and sisters. Melanie pulled her mouth from her brother's cock, trails of spit still connecting her lips to his shaft.

"Fuck that's so hot, Soph!" she said as she pulled herself up and mounted her brother. "You better share if you get you hands on that monster!"

"Hey-" began Marcus, his protest cut off by an animal groan as his twin sister's dripping pussy enveloped his cock. She put her finger to his lips as she began bouncing up and down on him.

"Quiet you, I didn't hear you complaining when I offered to share you with Sophie."

Sophie already had her hand down her tight booty shorts and her fingers buried in her pussy as the Chos started fucking.

"I couldn't even get my fingers around the whole thing, Mel!" she moaned as she touched herself. Melanie was biting her lip and holding her brother's head to her chest as he attacked her 32B tits with his tongue. His hands were ******* her ass as she rode him, kneading the soft flesh and giving her the occasional light spank.

"He was so embarrassed that I'd touched it though," Sophie continued. "he might not even want to fuck me. He was probably just turned on because that hot actress was getting her big tits out."

"Have you seen yourself, Soph?" asked Marcus, pulling his mouth away from his sister's nipple. "If he doesn't want to fuck you, he's gay." Melanie made a noise of agreement as she pushed her brother's mouth back onto her tits.

"Not everyone is into i*****, guys." Sophie continued. Her orgasm was fast approaching, and despite her trepidation it was the feeling of Jason's cock in her hand that was filling her thoughts as she plunged her fingers into her wetness.

"Not everyone is willing to admit they're into i*****." Melanie corrected. "Deep down, everyone wants to know what it's like. That's why i***** porn is so popular. Daddies want to know how it would feel to take their daughter's virginity. Mommies imagine training their sons to be the perfect lover. Brothers and sisters wish they could replace their siblings' partners. Nieces want to fuck their uncles, nephews want to fuck their aunts, cousins want to fuck each other at every family get-together. Hell there's probably more than a few grandparents who've thought naughty thoughts about their grand******** who are 'all grown up since the last time I saw you'. Face it Soph, we're the normal ones. It's the people who've never had i***** even cross their minds who are weird. Jason might not admit it, but he's thought about lifting you up, pinning you against a wall and fucking you until that pussy belongs to him."

The image of being helplessly held aloft in her brother's powerful arms as he ravaged her pussy pushed Sophie over the edge. Her orgasm ripped through her, making her arch her back to grind her clit against the heel of her palm. She felt herself squirt, pussy juices flooding her shorts and soaking the front of them. Marcus watched his friend and sometimes lover cumming on his sister's bed, and was suddenly overtaken with his own orgasm. Melanie soon followed, cumming as soon as she felt her brother's hot cum spurting against the walls of her womb. The twins collapsed back onto the bed together while Sophie peeled off her now soaked short.

"Mel, I might need to borrow some clothes before I go home."

*

When Jason arrived home he noticed that his mother's car was back in the driveway, which meant that she and Sarah had returned from their spa day. However, Sarah's car was gone, meaning that she had left again. He felt a deep disappointment that the was no chance of getting into his sister's pants today, but figured that he might as well use what was left of the evening sun to enjoy some time in the family's backyard pool. Slipping into the house and quickly heading upstairs, he changed out of his clothes and into his swimming shorts before going back down and out into the backyard. There he found his mother sunbathing near the pool on a lounge chair, only the top of her head visible over the back of the chair. She turned around and sat up when she heard the back door, and the sight made Jason's jaw drop.

To call what his mother was wearing a bikini would stretch the meaning of the word almost as much as the material was stretched across her form. Growing up Jason had only ever seen his mother in black one-piece suits. Because of her size she had always gone for bathing suits that offered a lot of coverage and came in slimming colours. What she was wearing at that moment, however, was a tiny red two-piece. The material of the top barely covered her nipples, and the bottoms left equally little to the imagination. Nearly every inch of her body, the body that had fuelled Jason's fantasies for years, was on show right in front of him.

"Oh honey, I didn't hear you get home! Where's Sophie?"

"I... Uh... She... Cho twins. She went over to the Cho twins for a bit." came the slow response.

"Oh that's lovely. I haven't seen Marcus and Melanie is so long, she really needs to invite them over here more often instead of always going to their house."

On the inside Alison was delighted. The plan had been to get Jason all hot and bothered seeing her in this tiny bikini, then invite him down to the basement to help her with some 'stretches'. Sophie would lock herself in the room for the evening, as she usually did, and wouldn't hear a thing if her mother was successful in getting her hands on her brother's fat piece of man-meat. Now that the youngest ***** was away for the evening, though, the trip to the basement was no longer necessary. The backyard was surrounded by high walls and most of the families around them went for long holidays during the summer months. Alison could seduce her son right there in the open and nobody would catch them. The thought gave her a little thrill.

"I figured I'd try and work on my tan a little bit. I know it's already summer but better late than never right? Are you coming to join mommy by the pool?" she lowered her sunglasses and fluttered her eyelashes at Jason as she asked.

Jason could feel his cock throb when his mother called himself mommy. She had been doing it a lot more in the last few days. He thought about the way Sarah had started calling herself mommy in bed with him after he let the word slip one night. Sometimes he wondered if his big sister knew he thought about their mother when he was fucking her from behind. Maybe she just thought he had a mommy kink, like the way many of the girls he had bedded in college had moaned for 'daddy' as he fucked them. Would she be upset to learn the truth?

"Hello, Earth to Jason?" Alison waved her hand in front of her son's dazed face.

"Oh right, sorry mom!" he exclaimed. "Sure, I was going to do some lengths of the pool and then I'll sit up with you."

"You're such a good boy." she smiled, and Jason's heart melted. "You'd be a great boy if you were willing to help your mother with her sun-tan lotion."

Alison gestured at the bottle on the table beside her. Without waiting for an answer she rolled herself over onto her front, allowing her son to see how the thin strip of her thong bikini bottom was completely swallowed by her ass. Jason didn't trust himself to speak as he sat on a small stool and grabbed the bottle. He poured a generous amount of lotion into his hands and began rubbing it into his mother's calves. Making sure every inch in sight was covered, he then moved up to her thighs and began massaging in the lotion, drawing a satisfied purr from Alison. When he reached the tops of her thighs he stopped, unsure of what he was allowed to do.

"Don't stop baby, you don't want mommy to burn do you?"

His cock twitched at the sound of 'mommy' and he dutifully continued rubbing the lotion into his mother's body. Now he was moving onto the cheeks of her massive ass, marvelling at how big it was and how much it jiggled under his hands. Alison could feel herself getting wetter as her son groped her ass, wondering if he was comparing it to Sarah's or those college sluts he was fucking. Several minutes passed by the mother and son like this, the lotion all but forgotten and Jason making very little effort to hide the fact that he was now just copping a feel of his mother. As much as Alison was enjoying the attention, she knew that she had to keep the plan moving.

"I think I'm covered there sweetheart, why don't you do mommy's back now. Here, I'll help."

With that she reached behind her and undid the strings of her bikini top, letting them fall to either side of her. Jason gulped loudly and did as he was told, rubbing lotion into every inch of his mother's back. Alison was still purring contentedly. It wasn't just from how horny her son's touch was making her, the young man was genuinely good at massages and his mother was definitely enjoying this one.

"I think your back is done now mom."

"Thanks honey, would you mind helping with my front too?"

Again, Alison didn't wait for an answer. She rolled herself over and sat up straight, her bikini top abandoned on the chair behind her.

"Mom!" Jason nearly shouted. The reaction was instinctual, but just below the surface he was absolutely delighted. He had stolen and cum in enough of his mother's bras to know she was a 46P, the biggest tits he had ever come across in his life. Years of questions about what those tits looked like naked were finally answered, and Jason was in heaven. It was all he could do to keep his face in a look of shock instead of a look of *******.

"They're just boobs honey. I'm sure you've seen your fair share in college and we're all adults here. I've been thinking about it and I really don't want any tan lines so they have to come out in the sun and they need lots and lots of lotion." Alison said, mock exasperation in her voice. Behind her sunglasses her eyes were absolutely glued to the massive tent in Jason's swim shorts.

So it's not just your sister that gets you going baby, she thought. Mommy's body turns you on too.

Jason couldn't believe his luck. A small part of him thought it was weird that his mother was asking him to rub sun-tan lotion on her tits, but the rest of him was beating down those thoughts and getting ready to feel the best tits in the world. Perhaps a little too eagerly, he filled his hands with lotion and began to massage his mother's chest. The earlier purr soon turned into proper moans as Jason's hands roamed over Alison's huge tits, moving down the massive mammaries until they stopped just above her large areolas. Alison grabbed her son's wrists and brought his hands downwards, his slick palms coming to a stop over her hard nipples. Jason wasn't stupid. He had quickly realised that his mother was getting off on the tit massage she was receiving and that thought excited him beyond belief. Still, he couldn't help rationalising this behaviour. His mother had been lonely since parting ways with his father, it had probably been years since a man had touched her like this. He figured she would probably enjoy the feeling for a while, then thank him for helping her with the lotion and they would never speak of it. If he tried to broach the subject now it might embarrass her. If he pulled his cock out and slid it between her tits like he so desperately wanted to, it would definitely embarrass her and maybe ruin their relationship. The best course of action, Jason reasoned, was to enjoy what his mother was allowing him to do until she had enough.

"I think that's enough baby."

Jason had to suppress a groan of frustration. He hadn't been expecting to have to take his hands away from those glorious mounds of flesh so soon. Alison, for her part, could have let her son grope her tits all evening. But the more she looked at the massive twitching tent in his shorts the more she realised that she needed his cock inside her as soon as possible. It was time for a final gambit. It would be hard to feign innocence with this one, but not impossible if she cried stupid should it fail. As Jason sat back she hooked her thumbs into her bikini bottom and lifted her ass from the chair, sliding them down to her ankles and kicking them away.

"I did say I wanted no tan lines, right sweetie? But the thing is, I read you're not supposed to use sun-tan lotion on your... sensitive areas..."

Jason was practically drooling as he responded.

"Oh, uh, what can you use?"

Alison smiled and spread her legs, leaving them on either side of the chair and leaving her pussy wide open to her son's gaze.

"Well, I did read that saliva can make a good substitute..."

This was the moment of truth. Mother and son both knew that saliva couldn't be used as sun-tan lotion. Jason knew that what his mother really wanted was for him to lick her pussy. And if she wanted him to do that, then she wanted him to fuck her. She wanted him inside her just as much as he wanted to be inside her. He stood up from the stool, and for a moment Alison was afraid that he would reject her. Then he made his way around to the end of the lounge chair. Kneeling down, he placed his hands on his mother's thighs and gently pushed them further apart before leaning in and flicking his tongue into her wetness.

Alison moaned out loud as she felt her son's tongue against her pussy lips. Spurred on by the taste of his mother's nectar, Jason dove into her womanhood and feasted like a starving man. She couldn't see him over the mass of her belly, but she was well aware of how passionately he was eating her out. She had never felt anything like this, not even with her husband. Jason knew just what she needed, the right time and angle to probe her dripping hole, when to flick his tongue across her throbbing clit, how long to wrap his lips around it and suck. His hands had moved from her thighs to her belly, and feeling his grip on the soft flesh of her stomach drove her even closer to orgasm. Jason began rapidly lapping at her clit and suddenly she could feel the pressure building.

"Suck on mommy's clit Jason, you're going to make me cum!"

Jason, ever the good boy, did as he was told. Alison clamped her thighs around her son's head and began bucking her hips, grinding her pussy into his face as she came. She knew it was a big one, and her big ones were always gushers. Sure enough, once she relaxed her thighs from around his head she could see that Jason's entire grinning face was dripping with her juices.

"Oh God baby, that was amazing!" she sighed

"You can say that again mom!"

Jason stood up and Alison could see that, if possible, the tent in his shorts had gotten even bigger while he was eating her out. Alison took off her sunglasses and curled her finger at her son, becoming him closer. She sat up again as he moved back around to face her, his crotch now level with her face.

"Poor baby, did helping mommy get her rocks off make you horny? Don't worry, mommy is going to take good care of this."

With that she pulled Jason's shorts down. His massive cock sprang out and slapped against her face, leaving a trail of precum along her cheek. Wasting no time, Alison immediately ran her tongue along the underside of the shaft, from the base up to the head. Then she engulfed the throbbing knob and began sucking it. Even with the first few inches in her mouth there was room for the horny mother to use both hands to jack off the rest of the shaft. She pulled off her son's cock, gathering the ropes of saliva with her hand and spreading them down the rock hard rod as she went to work sucking on Jason's bloated balls. She was rewarded with a series of expletives and moans, and his fingers entangling themselves in her hair. She brought her lips back to his cockhead and resumed her sucking, letting her son hold her head in place by her hair and thrust his cock into her willing mouth. Suddenly he pulled her off his cock. Before she could complain he leaned down and kissed her. It was deep and passionate, the kiss of two lovers, the intense feelings only exacerbated by Jason's hand keeping a firm grip on his mother's hair as they kissed and his saliva coated cock rubbing in the valley of her humongous cleavage. When he pulled away from his mother, his eyes were filled with lust and love.

"I love you so much mom, but I had to stop you there because you were about to make me cum. And I want the first time mommy makes me cum to be deep inside you."

"I was hoping you'd say that baby." Alison moaned in response.

She lay back on the lounge chair again as Jason got into position between her legs. He rubbed the head of his cock on her swollen clit, making her moan in anticipation. Then he slowly dragged it down through her wetness, stopping just as he felt the hole he had come out of 19 years previously. He looked up into his mother's face, seeing the anticipation and animal need written across it.

"Last chance to back out mom, are you sure you want this?" he asked.

Alison wrapped her enormous thighs around her son's waist, her feet resting on his toned butt, and squeezed her massive tits together for him.

"Please baby," she begged, thrusting her hips slightly, "please fuck mommy. Make mommy your fat cumslut with that big thick cock!"

Needing no more encouragement, Jason sank his cock into his mother's buttery heat in one swift movement. Her pussy was so sopping wet from his expert tongue fucking and the horniness of the taboo situation they were in that it offered no resistance to the massive invader. On the contrary, it seemed to drag the young man's cock ever deeper into the depths where he was conceived. His mother's velvet walls gripped and massaged his shaft, coaxing it to continue down through the wetness as far as it could go. That limit was soon reached as Jason bottomed out in his mother. All 10.5 inches of his monster cock was sheathed in his mother's pussy. He leaned down to kiss her again, loving the feeling of her big soft belly and huge tits between them as they made out.

"Mmmmmmmm fuck baby!" Alison moaned, breaking the kiss. "I can't believe I took the whole thing! You're the first cock in mommy's cunt in years and the biggest cock in mommy's cunt ever!"

Hearing his mother say 'cunt' made Jason's cock twitch, which brought renewed moans from Alison. She began thrusting herself up on her son's cock in earnest now, desperate to feel him really fuck her. Jason was happy to oblige, drawing his hips back until only the very tip of his cock was still inside his mother before driving his entire length home again. The backyard filled with the sounds of rough wet fucking, mother and son's moans mixing with the squelching of Jason's cock plunging into Alison's pussy over and over again. The horny mother was beside herself with lust, her nails dragging down her son's muscular back, her legs pushing against his butt trying to force him deeper into her.

"Fucking my son." she moaned, more to herself than Jason. "Letting my son use my cunt like a cheap whore. Such a big fucking cock, so much bigger than your dad's. Fuck baby I've needed this. You have no idea how badly mommy has needed a big fucking cock like yours."

"I've always wanted to do this mom." he moaned back. "I've been dreaming about fucking you since I knew what fucking was"

"Wish I had known about this monster cock years ago baby, mommy would have jumped you the second you turned 18. No college for my baby boy, no skinny little college sluts getting their hands on this perfect cock. Mommy would have kept you home forever. Cooking for you, cleaning for you, and letting you use her holes whenever you wanted. I'll still do it baby, I'll still be your filthy little mommy slave. All you have to do is never *************** like this!"

"Are you kidding mom?! I'm never giving up this pussy!"

Jason was properly pistoning in and out of his mother's dripping pussy now. Her juices were everywhere, coating both their thighs, dripping from Jason's balls, sliding down to Alison's asshole and completely soaking the material of the lounge chair. Jason barely noticed the mess, however. There were only two things captivating his attention at that moment. The first was the heavenly feeling of his mother's pussy milking his cock. The other was the way her massive belly rippled and jiggled as they fucked. It was hypnotic, every movement producing seismic waves in the soft flesh beneath him. Alison could see her son's fascination with her belly and she loved it. Keith had been the only man to love her fat belly up until now. Knowing her son was turned on by her entire body, not just her gigantic tits and huge ass, made her pussy gush a little bit. She knew her orgasm was fast approaching.

"Jason, baby, mommy is going to cum soon."

"Me too mom, I can't hold off much longer." he replied.

"Then mommy needs you to do something for her to speed this along, because I want to cum at the same time as my hung son does"

Jason looked up to see that his mother had gathered her massive tits in her hands and squeezed them together. She leaned her head forward and flicked her tongue out against one of her nipples, feeling her son's cock get even harder (if that was possible) at the sight.

"I need you to suck on mommy's tits like you did when you were a baby."

Alison had barely finished her request when her son attacked her tits. Her son's lips clamped around a hard nipple and began sucking like his life depended on it. His hips began thrusting faster and faster, driving the ********** couple ever closer to their respective orgasms. Alison took her own free nipples into her mouth, matching Jason's aggressive suckling, and suddenly her orgasm washed over her like a tidal wave. She moaned around her nipple, the vibrations adding even more stimulation. Once her orgasm had subsided somewhat, she grabbed her son's head and brought it up to look at her. Then she she repeated the words she had heard her daughter say to him less than 48 hours previously, the words that had started her on this journey of i*****.

"That's it baby, cum for mommy. Cum deep in mommy's pussy."

Jason groaned and buried his head in the soft valley between his mother's tits as he came. Alison felt rope after rope of his hot thick cum pumping into her womb as she held him to her chest. She had never before felt any man cum so much inside her in one go, her son's seed was completely filling her up. Eventually the last few spurts left his cock and she pulled his head out of her cleavage to kiss him. They made out passionately, just like he made out with Sarah every time he came inside her, their hands still exploring each other's bodies.

"I love you, mom." Jason said, breaking the kiss.

"I love you too, honey." Alison replied dreamily.

"What the fuck?!" screeched a voice from the back door.

Mother and son turned their heads in sync towards the back of the house. There, standing in the doorway, staring at her mother and brother tangled in the aftermath of their ********** fuckfest, was Sophie....