Six years after her divorce, Mirai's adult son Taro accidentally sees her masturbating late at night. Realizing that the cheerful, hardworking mother he knows is also a sexually frustrated woman, he decides to help. He asks his womanizing adult friend Shota, who knows how to please women, to sleep with her just once. Shota agrees, and Taro arranges dinner at home before deliberately leaving to shop. Alone with Mirai, Shota approaches her, brings her to orgasm with tongue kissing and oral sex, then leads her to the bedroom. Initially hesitant, she grows increasingly aroused under his skilled touch.