Sally couldn't bear the thought of her son leaving for college. She thought that once he left the nest, she'd lose him forever. If he went out into the world, he'd forget about her and then she'd never see him again. She wanted her baby boy to always need his mommy. She loved her son too much to just let him go. She knew she had to do something to make him stay.
After a long day of school, Sally's son got to his house to find it empty. He figured that his mom was off running errands or something so he went to his room for a quick nap before dinner. He entered his room to find his mom naked on his bed with her legs in the air. She spread her legs seductively displaying her wet fertile pussy, beckoning him to come closer. After a long pause, he quickly began to undress, freeing his big stiff cock from his pants.
She knew he couldn't resist his mother. Sally's son thrust his cock into her dripping fertile cunt with reckless abandon. He shamelessly pounded his mom hard into his bed. Sally felt as if his big thick cock was made for her pussy. Every stroke was like heaven; her son's big cock hit every single pleasure spot on the way in before kissing the ring of her cervix with its tip. Sally screamed as her son gave her the best fuck she's ever had. Soon, her son's pounding brought her to an intense orgasm. Sally wailed as she covered her son's virile shaft in her cum. Her orgasming pussy spasmed uncontrollably, milking and squeezing her son's cock, practically begging for him to blow his load inside.
Watching his mom cum on his dick as he fucked her quickly sent him over the edge. He knew he couldn't cum inside her; he would throw his whole future away if he got his mom pregnant. He tried to pull out but before he could Sally wrapped her legs around his back trapping his big spasming cock inside her unprotected pussy. Sally cooed for her son to relax and cum inside as he moaned and squirmed unable to escape. He reluctantly erupted inside her, shooting rope after rope of his hot sticky seed deep into her fertile womb.
Completely drained after their intense fuck, he collapsed into his mother's arms. His cock spurted lazily inside her, slowly emptying the last of his thick potent cum into her unprotected pussy. Once she was sure that his balls were empty, Sally rolled her sleeping son off of her. Sally kept her legs in the air to make sure every last drop of her son's precious potent seed found it's way into her womb. As her son's seed churned in her tummy, Sally swore she could feel each time one of her son's energetic swimmers fucked its way into her eggs, planting one of his siblings in his own mother's belly. She couldn't help but rub her clit and moan as her son's seed worked its magic in her fertile womb.
Two weeks later, Sally sat on the toilet in suspense as she waited for her pregnancy test to finish. Finally, after what felt like an eternity, the results became clear. Sally was elated when she looked down at her pregnancy test to see two red lines! Overjoyed, she rushed to her son to break the news to him. Feigning regret, she informed him that he had knocked her up and how she would probably need help caring for the baby. Sally had him right where she wanted him; she knew her baby boy wouldn't leave her now.
Months later while his graduating class moved away, Sally's son stayed behind with his mother. He was devastated having been left behind by his friends and classmates though having a hot pregnant mom to keep him company certainly made things more bearable.
In the short few months since her impregnation, Sally's belly has swollen into a huge pregnant dome filled with five of her son's big heavy babies. Weighed down by her enormous belly, Sally waddles around the house struggling to do her daily tasks. Though she didn't seem to mind, she thought carrying five of her son's big incest babies was a small price to pay to keep her precious baby boy around.
Sally loved having her son around all the time. She loved having someone to help out around the house. Someone to rub her aching back and massage her swollen feet while she rubbed her huge baby bump, soothing the active kicking grandchildren inside. Someone to give her the big babymaking cock that made her so big and round in the first place.
Now that Sally is too pregnant to work, all they can do is lounge around the house and fuck all day. Sally always had to keep one hand on her huge pregnant belly to soothe her kicking babies while she bounced on her son's big hard cock. Her babies always seemed to get so riled up while she was fucking her son. They'd all go into a frenzy, kicking and squirming while she rode her son's big babymaking shaft; they definitely knew who their daddy was.
Sally's son slowly adapted to domestic life with his mom while they waited on the arrival of the quintuplets. He's currently looking for a decent paying job to help provide for the five new siblings he fathered. He hopes he can find a good job and fast because he has a feeling that soon after she delivers he'll be put to work fucking another set of siblings into his mama's fertile tummy.
Idea submitted by @Zaloog81