There’s a small village in the valley. A girl there hangs to death inside an old school building. Her name is Kirishima Kaede. Before the incident, she confides in her childhood friend, Takahashi Aoi. She opens her heart to him. Her pouting face remains in Aoi’s memory—as do her laughter and the things they did, bodies pressed against one another. Aoi remembers something that rouses his suspicions. Aoi deeply believes that someone killed Kaede, and he leaps into action. One day, when Aoi is pondering his thoughts alone in a classroom, the mysterious transfer student, Minazuki Ajisai, calls out to him…