This occurred when Makoto was a trainee at the school. Yurina Ryokaze, a popular teacher who teaches drawing to students in the art classroom, is married and her husband works alone in Italy. Her father, the owner of the gallery building, has fallen ill and she has been assigned as a temporary teacher at the school until her condition improves.
Sakakura, an upperclassman from his college days who introduced Yurina to the school, feels an unusual affection for her, and a plan is put into motion to train Yurina in complicity with Yasuno, with whom they share a mutual sympathy. Yurina receives an order from the director to participate in an exchange workshop. On the day of departure, Yurina drinks a cup of black tea recommended by Sakakura, but she feels dizzy, her eyes darken, and she faints.