A forbidden love story between Chiharu, a fifty-year-old mother who is treated like a servant by her husband, and her son who feels pity for such a mother. Her son's marriage is decided, and Chiharu masturbates to her son's underwear to distract her from her lonely feelings. On the very day her son leaves her home to live with her fiancée, her mother Chiharu can't control the thoughts she has in her heart and turns them into her actions. She seduced her beloved son...
