Miyu Kanade, a popular office lady known for her well-proportioned body and intense performances, faces a dramatic downfall as she becomes an anal cumdump due to financial desperation. To support her husband, she gets involved in embezzling company funds, leading to her forced descent into humiliating anal training. When her husband falls seriously ill and mounting medical bills overwhelm her, Kanade accepts help from Hirota, a business associate, who offers a way to cover the expenses. Despite knowing it's wrong, she agrees out of sheer necessity—but the scheme is leaked to the company president. As punishment, Kanade is condemned to have her anus violated and exploited, thrust into a life of degradation and sexual slavery.