Yu and Shinya are a close-knit, loving couple. However, due to their age, Shinya's erection is poor. Afraid of disappointing Yu, Shinya decides to rely on a powerful aphrodisiac, but Yu and their son Hayato accidentally drink the aphrodisiac-laced drink. The sudden surge of carnal desire is so intense that it overwhelms their reason and consciousness. The body, having experienced overwhelming pleasure, cannot forget the stimulation even after realizing the aphrodisiac was the cause.
