Two years ago, Chisato lost her beloved husband in a traffic accident. After his death, her son Ryo suffered a mental breakdown, stopped attending school, and became a shut-in. Grieving and anxious, Chisato began installing hidden cameras throughout the house to monitor her son's daily life. Ryo, now isolated in his room, spends his days masturbating in solitude, secretly watching footage of his mother changing and her private moments. One day, Ryo discovers that Chisato has begun an affair with his homeroom teacher. Shocked and enraged, he is horrified by his own circumstances—and consumed by conflicting emotions that blur the line between hatred and desire.