Yuko, a mother who lives at her daughter's couple's house while her husband is away from home.She lived a lonely life without seeing her husband, but she wasn't the only one who was lonely.Her son-in-law, Toru, is always masturbating alone in the middle of the night.Yuko, who knows the pain of her sexual desire not being satisfied, tells him that her daughter's responsibility is her own responsibility, and invites him every time.However, in order to satisfy her own sexual desire, she continues to seduce him all the time because she wants a big cock for her son-in-law.