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Hi, I’m Ethan and my sister is an absolute menace to society and always has been. It all started when I was 11 years old and my mom came home from the hospital. She was a large breasted woman, always has been since she was a girl. My 10 year old little sister Melany inherited her mom’s genes, her breasts in proportion seem relatively the same as mom’s, each one were about 3 times bigger than her head. Mom brought home our little sister Cady in her arms against her breasts, but oddly me and Melany were both curious about Cady, specifically why her lower half was draped in a cloth that bulged with something inside of it that looked bigger than her leg.
I was repulsed and caught off guard by the pulsating shaft that throbbed under the cloth that draped Cady’s legs. Mom explained to me about the family’s hyper development disorder which I understood already, but Mom elaborated by explaining that Cady has both the hermaphrodite gene combined with a cock strand of hyper development disorder. I felt it was unfair, Cady gets a cock with hyper growth disorder and I don’t, mine was always below average.
I could tell that Cady was enjoying the view of her mothers and older sister's assets, her eyes were glued onto them and her tenting erection started growing even bigger. Throbbing under the cloth was a large 8 inch baby cock with big chicken egg sized balls underneath that hung past where the cloth ended as the erection lifted it further. Mom’s eyes were glued to her daughter’s dick under the cloth, its tip pressing against the cloth made an irresistibly delicious looking outline that made mom’s mouth water as much as the tip of my sister’s dick drooled out pre.
Mom made an excuse, she had to take my sister into her bedroom and take care of Cady’s massive erection, doctors orders. That same doctor was impregnated by Cady and I wouldn’t have gotten that news till weeks later. My mom brought Cady into her room despite Melany’s protests to have a sleepover with her new little sister first. I couldn’t explain how shocked I was to be hearing this at the time and watching my mom take Cady into her room, kick my dad out and started slobbering on my sister’s dick.
Cady was oddly strong for a newborn, any normal month old would have been crushed by an adult woman with large fat breasts and equally giant ass and thighs slamming down onto them while riding their daughters monster cock, but Cady always was able to take it without getting hurt oddly. Part of her strand of hyper development syndrome was that her body would become inhumanly strong, that explained why her body could handle having her giant 8 inch cock being fucked.
When Cady came it was audible, with each cum blast inside her womb my mom would twitch and undulate in pleasure . . . and that was how mom got pregnant again. Melany also started having her fun with Cady, their once a week sister sleepovers involved Melany learning to suck dick, Melany learning to use her feet to massage Cady’s dick and Melany getting her insides pelted with cum as a hard baby dick ruts inside of her.
As Melany became pregnant and mom’s pregnancy went on Cady only grew bigger and stronger. After a few months Cady started being able to thrust her hips during sex, grapple and grab hold of mom and Melany as she fucked them. Grabbing mom’s hair was always Cady’s favorite thing to do, she smiled so happily when she did it too.
Cady never wore a diaper either, all of them would break easily from Cady’s giant erections which eventually grew to 10.5 inches long at 6 months old. Eventually accidents did happen. . . and Cady would unleash her giant bladder and flood a corner of the living room or kitchen in golden showers. Mom did her best to keep Cady clean and to clean up her messes, but Cady’s cock always stank of jizz and there was no way to get rid of the pungent stink.
Eventually Cady barked her first word during one of mom’s cock sucking treatments to Cady’s large heavy erection, “Fuck”, it caused mom to suddenly stop aggressively sucking and drooling on her daughter’s nuts to look at her, then mom rewarded her by hopping on Cady’s cock and riding her pussy on it till Cady blasted her insides with her heavy nuts.
Cady’s kids inside of Melany and mom were growing the same as Cady, mom carried 3 while melany carried 2, and all 5 were hung little monsters just ready to be born. Eventually mom and Melany felt their babies fucking inside of them, they convulsed in pleasure as their brats screwed inside their wombs. This went on for a few months with the outlines of the hung herm brat dicks straining their bellies.
The house smelt of Cady’s jizz and piss, and both moms and Melany’s beds were caked with it. The odor didn’t deter babysitters though, nor did Cady’s huge cock waving in front of her legs as she learned to stand and walk rather quickly. Cady was raising her voice more as she said “Fuck” putting her whole lungs into it as she began to slam her pelvis into the many babysitter suitors she’d have over, and each one left with multiple hermaphrodite hung babies growing inside of them.
I tried to protest what was happening since day one, but none of them ever listened to me. I eventually learned to live with all of this instead of running away, but even if I ran away then I eventually wouldn’t have gotten far. So ends the first year of my life with Cady in it, the first girl diagnosed with hyper development disorder at unprecedented high levels.