The first adult mother-and-son role-play in the series stars Nagase Ryoko as a loving mother living alone with Ken, her naïve and clingy adult son. When the sexually inexperienced Ken proudly shows her his morning erection, she gently teaches him how to masturbate. Soon she cannot resist taking his cock into her mouth for his first blowjob. When he pushes inside her as she lies in bed, she lets it continue and turns it into a hands-on lesson in baby-making sex, amazed by how much her grown son—and his cock—have matured.