Yoichi loves his wife Yuko very much, but she hasn't been feeling well lately. Worried that Yuko will lose interest in him if he continues like this, Yoichi secretly buys an aphrodisiac. However, while Yoichi is away, Yuko and their son Kota drink the drink containing the aphrodisiac. Yuko's body heats up and her uterus starts to ache, and Kota gets an erection, so they gradually lose their minds and passionately desire each other, leading to a physical relationship. Drowning in pleasure, the two realize that the aphrodisiac was the cause of their mistake, but...