57-year-old Reiko has not had any sexual activity with her husband for several years. One night, while masturbating in her bedroom, she is discovered by her son. Embarrassed and confused, she ends up witnessing his masturbation as well. Suffering from sexual frustration, Reiko begins to see her son as a man who can fulfill her desires, and starts pursuing a new kind of relationship with him. The story portrays her complex and conflicted emotions.