Futaba Yoshioka (Natsuki Deguchi) and Kou Mabuchi (Kaede Sakurai) gradually draw closer to each other's feelings and come into close contact on the day of the cultural festival. Futaba, who wants to know Kou's true feelings, resolves to convey her feelings to him. Just then, Yui Narumi (Karin Fujiyoshi), a classmate Kou met in Nagasaki when he transferred during middle school and who shares the same sadness, appears before them. Unable to leave Yui, who knows the same sadness, alone, Kou embraces her in front of Futaba and Toma Kikuchi (Ryosuke Sota). Their youth is just one millimeter away, yet so distant.