Misaki (Hazuki Tsuchiya) starts attending high school and falls in love with a boy (Yuki Hashiguchi) commuting on the same train who is a senior at her school. He always takes the same train and stands grasping the same strap every morning. One year passes without any conversation, and he graduates. That winter, Misaki misses the train and finds him on the next train. He is standing in the same position. At last, Misaki starts to make approaches to him. Each day, she shifts the strap one by one to get closer to him.
Kumiko (Mariko Shinoda) lives alone in Kurume City. News arrives that her father has been hospitalized with cancer. Lying on the bed, he orders Kumiko to "Bring your boyfriend," but Kumiko has no lover. Kumiko goes to a matchmaking party and meets Tsuda (Daisuke Kikuta), who is three years younger than her. When Kumiko is invited on a date, she asks Tsuda to meet her father. "Did you go out with me to reassure your father?" Kumiko cannot answer. The separate emotions of the three characters are united by the memory of a fireworks festival at the Chikugo River.