Yukino is a housewife living with her elite bureaucrat husband and their college-aged son. Obedient to her husband's strict demeanor, she treats her son with equal severity, though she feels exhausted by a life spent merely following orders from her parents. One day, her husband declares, "It's about time you start thinking about your future partner," and begins an abnormal education by teaching his son how to have sex. Shocked by this instruction, the son loses his rationality and starts directing his sexual desires toward his mother, Yukino, whenever his father is away. As the family's relationships gradually collapse, a new drama unfolds.