Yukari and Hiro appeared to be an ordinary mother and son from the outside. However, Hiro harbored abnormal feelings for his mother, Yukari, to the point of using her as material for his masturbation. This forbidden desire had remained locked deep within him. Meanwhile, Yukari, tired of her emotionally distant husband, had begun an affair with her boss, Sasaki. One day, Hiro accidentally discovered his mother in the midst of her affair with Sasaki. Witnessing his beloved mother's infidelity, Hiro lost control and exploded in rage...