A single-parent family's life improves after the mother's remarriage. However, her new father, Kazuo, is a very naughty man, and his daughter, Aiko, is often peeped in the bathroom. At night, they have sex like beasts, and Aiko's mother Keiko's moans trouble her ears. Perhaps in order to get rid of those days, Aiko begins a relationship with her teacher, Ando, and they begin a violent affair. It seemed as if it was an imposition on Kazuo and Keiko... But, that day, Kazuo came home in the middle of the incident...
