The novel opens with a description of the oyster restaurant, which is famous for its oysters. Aiba kun, the new mother of chiharu, is waiting for her son at the restaurant. She tells the narrator that she has been invited to be his mother for the first time. The narrator is surprised to learn that the two men have gotten along very well, and that chiharu has learned from his father that he is getting married. He asks if Aiba's mother is getting mad, and the narrator says that she is. He wonders if she gets mad because she is a bad mother, and wonders if it means that she and chiharu are still seeing each other. He says that he has never thought of becoming a part of the family before, but that Aiba is his new mother. He then wonders if the marriage will change anything for the couple. He worries about the remarriage, thinking that it will not change anything. He mutters, "I'm fine," and mutters that this is his chance to show the reader his good side, too.