Ema, who had been working in the entertainment industry in Tokyo, suddenly announced her retirement and was living a decadent life at her parents' house in the countryside. One day, she met her stepbrother for the first time in several years, and he was a virgin who was constantly masturbating. He was so excited by his sister's defenseless, no-bra figure that he attacked her and they ended up having sex. Ema also has sex for the first time in a while. It feels so good that she climaxes and then has sex with him again and again.