Setsuna realizes that Haruki has been staying at Kazusa's house this whole time, and she reveals her true self to him: cowardly, introverted, and pathetic. But Haruki accepts her as she is. The boundary between them is broken, and the bonds between the three grow stronger as the school fair draws near. But Kazusa is skipping sleep and food to work on her "last trick" before the school concert.

Haruki hears about Kazusa's moving from her mother, who she hadn't been on good terms with. He feels betrayed and angrily confronts her. But his words force open the door to Kazusa's heart, which she had desperately tried to keep closed so that the three of them could stay together.