Futaba, who was embraced by Kou, is interrupted by a call from a girl who calls Kou "Kou-chan." As the cultural festival approaches, Futaba, invited to Toma's live performance, finds herself moved to tears by Toma's song, which resonates with her current feelings. Kou, who is with her, tries to speak to Futaba, but... On the other hand, Shuko, who has come to Yoichi's place, takes an unexpected action. Just one millimeter away from youth—will their feelings for each other truly come to fruition?
At the end of the first year of high school, Futaba Yoshioka meets Kou Tanaka who was her first love. In their middle school days, they attended the same school, but he suddenly transferred to another school. Three years later, he appears in front of her again with the different last name of Kou Mabuchi. His personality also seems to have changed from warm to cold. He is like a totally different person from three years ago. Futaba Yoshioka slowly learns what happened to Kou Mabuchi for the past three years and she become to have feelings for him again.
