My son's friend seduced me

Recently when David, our son’s best friend was over I called out asking what he wanted for christmas.
David wandered into my study wearing just his undies. I was a little embarrassed and it was when he sat down that I could clearly see that his penis was held against his leg by his tight undies. I must have looked surprised when I simultaneously realised that his penis could have been 7 to 8 inches long, running along his leg but held firmly by the tight white stretchy fabric. He bulged with no shame as I stared for a brief instant.
That night I couldn't help but think about how large David was
The following day, as usual David was over and I called him into my study again and gave him his christmas present. New undies I had bought for him, black ones, and asked him to try them on for me, to see if they fitted properly
He was soon back to show me.
I walked over and ran my hands over them-do they feel like a good fit David?
“Yes Mrs R”
“They're not too loose for you then”?I whispered as I ran my palms over his thighs. Walking behind him I continued to run my hand over his inside thigh. His legs straightened as I felt his generous penis under my hand. My index finger ran the length of his bulge
Placing my hand on his waist band I slowly slipped down over the full length of him feeling his penis harden under my soft grasp
“They're good” he said with some small stress evident in his voice
I walks around him, and faced him directly
My leg…. clothed in a sheer dark stocking…. slipped between his gently, so i could feel his warmth
He closed his eyes...
The heat from his thighs and particularly from his evident erection warmed my thigh as I stood now on my tiptoes to allow my thigh to massage against his stiff length
David put his hands on my waist to steady himself as he shook a little...his eye-lids fluttering as i stared at his face
I looked down and saw he had grown even longer, the head of his erection at the verge of exposure.
Then...white cream oozed through his undies onto my sheer stocking. “Oh Mrs R...oh….”
Taking a tissue from my desk I placed it in his hand. David opened his eyes and slowly wiped the cream from my stocking. Wiping my thigh all the way up to my hem line.
“Is that the best you can do” i questioned
He hesitated...then bent down and licked my wet stocking
“Good boy” i whispered into his ear
“Now go and have a shower like a very good boy”
Minutes later I could hear the shower followed by the shower door as David got in...
I tapped at the bathroom door
Then quietly let myself in
The glass was a little steamy, his new undies were on the floor. I stood for a while as David had his back to me, his hands busy...washing himself...
I stopped and picked up his new undies, they were wet down one leg and smelled like him.
Tasting the wet area of the black lycra with my tongue just a little, I dropped them to the floor. My fingers slowly pulled my zip down allowing my skirt to fall off me...
“David can I come in” i whispered
“Yes” he said-and i stepped in still in my blouse, bra, panties and stockings
David still had his back to me and i took up the soap and began to soap his back in small circles
The water ran down thru my blouse and bra and then thru my panties and over my stockings
It felt warm and i stood exceptionally close to David feeling the moment
Pressing lightly against his back, my pelvis occasionally touching him as I moved
Then nervously he reached back with his hands and held my sides timidly
My soapy hands skillfully caressed his sides, round and round. Gradually around to his stomach. “That nice”? I enquired.
“Yes” he said
My fingers ran over his erect nipples... “Mmmm erect” i whispered
“Mmmm” he said shakily
My nipples were also erect and protruding against his muscular back as i moved my breasts against him to stimulate myself more
Letting one of my hands drop down to feel his erect penis
David moaned “Mrs R….”
“What now”? i asked
“Wank me...”
“I beg your pardon David”
“Wank me please Mrs...” he begged
My heart was beating so fast in my chest i could see my breasts move up and down
My fingers encircled his shaft, then ran back and forth along his full length
“David you're very big...should we...”
David still holding my sides let go and turned toward me as I quickly turned away from him to face the glass, my hands dropped to my sides, no longer feeling how hard he had become
David’s body pressed me against the shower glass almost violently. The water still running over us both
His erection forced between my legs and rubbed against my drenched panties
His hands pulled at my panties as i protested
“No penetration David!”
The thin nylon ripped, now his erection was directly against my labia.
“David...too close….maybe not”
An intense internal sensation forced itself over me. I felt my labia gush over his shaft as my legs began to buckle
“No David, we mustn't” I begged
I spread my legs a little more for balance
His swollen penis head ran over my drenched vagina while my fingers reached down to control him. My breath panting in rhythm to his thrusts
“Wank me more” he insisted

Without warning pulling himself free of my control... David thrust his rock hard penis between my labia, slipping up inside me so far I gasped as I held his pelvis hard in against mine
He held me from falling as his erection drove deep inside me
“David no!”
“My cock is so fuckin hard” he exclaimed
Then silence as tension grew to a strong shudder between us, gasping as I orgasmed with the feeling of his semen ejeculating into me without control
My legs still shaking I moved over to the door and exited the shower. Semen still running down my thighs i quickly ran back to my room.