Parents caught me and my sis

me and my s*s were having sex on the lounge room carpet when our parents walked in on us, we weren't expecting them home. they said they knew we were having sex for ages, they could hear us in the bedroom. they said they were fine with it so long as s*s took special pills so i wouldn't get her pregnant. i asked if mommy took pills. they said no, they were trying to have another baby, but it wasn't working. they were wondering if i could give mommy a baby. i asked how. mommy took her clothes off and lowered her big hairy vagina onto my hard penis. "put your big dick inside your mommy's vagina and shoot your young sperm into mommy, your sperm will fertilize mommy's egg", mommy said. "is that how i was made?" i asked "yes, she said, i pushed you out of vagina, just like your sister. maybe you will make another baby sister in my womb". mommy slid slid her sopping wet pussy lips over my dick as she talked, and put my hands on her c***d-bearing hips. i slid my dick into mommy's pussy and pulled her closer, burying my dick deeper inside her until our hips touched an her pubic hair meshed with mine. mommy gasped in surprise "my son's dick is so big!" she cried, and dad laughed as he got ready to pump his dick into my sister's pussy. i watched my sister's face as she gasped, struggling to take daddy's penis as he pumped his dick faster. "mmm yes", she moaned, "like father like son - my son!!" i grapped my mommy's big breasts and sucked on her big nipples, just like when i was a baby. mommy moaned, "yes my baby boy, suck mommy's titties! give me a baby so i can fill them with milk for you!". daddy licked my sister's perky little nipples and she squealed in delight. mommy was breathing heavily and shaking as her pussy clamped down hard on my penis. i could feel my balls tighten, I hugged mommy tight and felt jets of sperm pump from my balls through my penis deep into my mommy's womb. mommy gasped as my warm sticky sperm filled her pussy "YES!", she screamed, "so much yummy sperm to make our baby!". daddy pulled his dick out of sister's pussy and grunted as he shot jets of warm cum across sister's face and belly. i kissed my sister, tasting daddy's sperm. mommy made me keep my penis buried inside her until my sperm found her eggs.