Ryu Enami, a virtuous married woman, goes on an overnight hot spring trip with her husband. Her only concern is that her older husband has recently developed ED, leaving her increasingly unsatisfied in their sex life. At the inn, she gets caught in an incident she must keep absolutely secret from her husband. She's taken advantage of by malicious men staying at the same lodge, who use her however they please. Unaware at first, her body is violated, and she experiences the unimaginable—her anus, untouched even by her husband, is invaded.