This role-play is performed by adults. Yu and Shinya are a loving couple. However, perhaps because of his age, Shinya's erection is poor. Afraid of being disappointed, Shinya decides to rely on a powerful aphrodisiac, but Yu and his son Hayato accidentally drink the aphrodisiac drink. The two of them desire each other so deeply and intensely that their reason and consciousness fly away from the sudden rush of lust. Even after discovering that the aphrodisiac was the cause of her body's overwhelming pleasure, she still couldn't forget the stimulation...