Single mother Yuko struggles daily raising her two sons, Yukiya, a kind and honest university student, and Kota, a mischievous and rebellious troublemaker. While Yuko constantly punishes Kota for his bad behavior, his attitude shows no signs of changing. One day, after catching her masturbating, Yuko decides to discipline him once and for all by luring him to her bed under the pretense of punishment. Using her voluptuous body to tease and torment him, she begins to sexually punish her son. Unnoticed, Yukiya watches the scene unfold, consumed by jealousy and rage, eventually intervening and joining in. A twisted web of incestuous desire, complex emotions, and dark family secrets ensues.