Chiyomi Horikiri lives in Shonan, a town close to the sea, and is currently competing in her last basketball qualifier for the prefectural championships in high school. With her mother Kaede, grandmother Yuriko, father Shintaro and younger brother Takuma watching over her, Hiroyuki Minami, a childhood friend of Chiyomi, her boyfriend and a basketball star, rushes to the gymnasium to cheer her on when an opportunity finally presents itself for Chiyomi, who has always been a substitute player. Unfortunately, Chiyomi lost the match, leaving her feeling relieved but with a hint of regret. Minami offered words of comfort and encouragement to Chiyomi… The always perfect Minami made Chiyomi feel a little anxious. Soon after, Minami’s college basketball team would have a game. Chiyomi who is going to cheer for the team and Minami made a promise to each other after the game.