He loves Kanna, his thoughtful and devoted wife, despite the twelve-year age gap between them. Yet their sex life has dwindled to once or twice a month because he can no longer stay hard until the end. Kanna assures him that simply being together is enough, but her sexual frustration is obvious. Desperate to see her passionately satisfied again, he discovers a wife-sharing fetish and becomes aroused by the thought of letting another man fuck her. From that day on, he begins putting a plan into action.