Convinced that his painfully shy adult stepsister will never tell their parents, he secretly plays with her nipples every day. She resists and blushes at first, but the relentless teasing makes her so sensitive that the lightest touch leaves her drooling and climaxing. Once he has conditioned her that thoroughly, he decides penetration will be easy. He teases her nipples all day, then fucks her until she cums repeatedly, reducing her to his obedient sex slave. To him, training the adult stepsister close at hand is easier and more satisfying than trying to find a girlfriend.