Just In All Stories: Johnny walked over to the machine. Johnny let out a tiny moan. Mary was rubbing Susan's pussy softly. Bobbing her head up and down her brother's cock Mary used her right hand to play with his balls, while her left hand went into her pants and underpants so that she could finger herself while giving Johnny a blowjob. Watching Johnny get undressed Susan and Mary took their own cloths off, Once naked Mary and Susan check out their new penis and balls jerking then selves off a bit. Gasping in pain at the intrusion in his ass Johnny opens his mouth as wide as he could, only for Mary to shove her cock into his mouth and begin to fuck his face.
Meanwhile with Susan she grabs Johnny's hips and starts to fuck his ass as hard and as fast as she could.
He tip toed past his parents bedroom and to his sisters lab. Pulling her left hand out of her pants Mary moved her mouth up until it was only covering the tip of his cock. Swishing it around his mouth he spits Susan's ball out and starts to suck on the other one. Moving down from the head he licks down the shaft to her balls where he puts one into his mouth and sucks on it. After a while he takes her balls out of his mouth and moves back to her cock. Taking the head into his mouth he sucks on it before engulfing her entire rod into his mouth and starts to suck her off.