Kanna, a former honor student turned delinquent following her parents' divorce, finds herself trapped in a twisted power dynamic with her teacher, Ren, and her friend, Mei. While Ren secretly obsesses over Kanna and prepares to marry her mother, he subjects Kanna to relentless sexual harassment both at school and home. Despite Kanna's desperate attempts to prevent the marriage, she is manipulated into a shared encounter with Ren and Mei, only to discover that while the wedding is postponed, Ren will still be living under her roof.