In this chapter, the narrator tells us that his older sister, Kisara, had her first sexual experience with him when she was a young child. Kisara is now engaged to a man named daiki, and the narrator wishes that she and daiki could not have sex together. He feels that he is a "filthy person" and wishes that he could not be with daiki. When he wakes up the next morning, he finds that Kisara has told him that daiki has been having a hard time at work, and that she wants to know why he is always making her do things that are "despicable" to her. The narrator says that he has avoided daiki before, but yesterday he was able to convince himself that he can count on Kisara to help him. He tells Kisara that they will be meeting closer to school, and Kisara thinks that this will be fine. When she realizes that she is being seduced by daiki every day, she feels a "swelling fidget" in her body. She feels that something is "awakening inside" of her, but she does not know what to do.