Futaba lost her first love, Kou, in middle school when he suddenly moved. In high school, she met a guy who resembled Kou, but has a different last name. She needs to know if he is the same guy, and why he moved without letting her know.

When she was in middle school, Yoshioka Futaba met Tanaka Kou whom she had mutual love. After Kou moved to Nagaski with his late mother, Futaba lost contact with him. In her first-year of high school, she met Kou who's now carrying the name "Mabuchi", who is now stoic, cold, and totally different from the gentle Kou he met in middle-school.