Chaste wife Ryu Enami takes an overnight hot-spring trip with her husband. Her only concern is that her older husband has recently been struggling with erectile dysfunction, leaving her increasingly frustrated with their sex life. At the inn, she becomes caught up in something she can never let her husband discover: a group of predatory men staying there force themselves on her. Though she knows it is wrong, her body still responds. Eventually, they forcibly anally fuck her, violating the one place even her husband has never touched.