Yoko, who was dissatisfied with her husband, Kazuichi, whose energy has declined due to her age, is overwhelmed by her old boyfriend who met at the alumni association for the first time in a while. Keita, a son who was suspicious of Yoko who was strangely excited, sees the scene where he promises a date. Keita, who felt lust for her mother's face, attacked her unbearably. At first, Yoko was reluctant and desperately resisting, but her body reacted to Keita's relentless caress and crossed the line between parents and children. Gradually, Yoko began to accept Keita ... The destination of the two who overrun the feelings of her husband, Kazuichi, and was driven by lust beyond the boundaries of parents and children.