Custom: He's experimenting with potions at his friends house. He's finally discovered how to turn into the famale version of himself. He's down to the last 3 ingredients and records his findings. It works! Well, sort of.... Some of his friends sisters DNA must have found its way into one of the test tubes... And he's turned into her! He can't handle what has happened to him, and his friend finds him. Little does he know, his friend and his sister have a much closer relationship than he could ever have imagined, and with an empty house, he soon finds out. One thing leads to another and he gives in to the amazing feeling of a cock inside him!