His older brother, Ryuta, was a half-withdrawal person, and had a sexual relationship with his younger sister, Nene, a female student. Nene knew that was a bad thing, but she couldn't refuse the kind Ryuta, and although she hasn't inserted it for years, she continues to have oral sex. One day, Kameda, a friend of Ryuta's student days, visits. Kameda noticed Nene's big breasts, threatened her relationship with Ryuta as a story, and planned to build Nene ...
