Lily has a younger brother, Shingo, whose appearance and personality are the complete opposite of her gentle husband, Shinpei. His job is unstable and he has no money, so he often comes to Shinpei to borrow money. One day, Lily is sent to deliver money to Shingo's house on Shinpei's behalf, but when she is led to a dirty room, she is suddenly pushed down. Lily is unable to move as Shingo, who is well-built, covers her and rapes her from behind. However, Lily feels a pleasure that she has never experienced with her husband when he penetrates her from behind.