Four childhood friends, Mikihiko, Keiko, Iyo and Miya, drift apart as they enter high school. Mikihiko, who excelled in both sports and study, manages to fail his high school entrance exams, shattering his identity. Keiko, who missed the first month of high school due to an illness, hears from Iyo that the group are hoping to reunite and rekindle the bond they shared as children.
Four middle school students, Mikihiko Inaba, Miya Natsuki, Keiko Futatsumori, and Iyo Hikawa, face the inevitability of leaving their small rural town to pursue a high school education. The four friends grew up together in Nishidori, a town fated to "disappear" due to its declining population and opportunities, something the four come face-to-face with when their favorite restaurant suddenly closes. Hoping to create new opportunities for themselves beyond Nishidori, Mikihiko proposes they take the Tokyo high school entrance exams.
The story skips ahead several months. Keiko is discharged from the hospital, having been admitted for the sudden worsening of a congenital heart condition. On her way home, she sees the silhouette of Mikihiko but is unable to call out to him. Later, she attends her first real day of high school, having missed the first month due to her time in the hospital. Though she managed to pass the entrance exams to attend a school in Tokyo, Keiko instead chose to attend a smaller high school alongside Mikihiko and Iyo. After her first day, she asks the faculty about Mikihiko and learns that he has not attended a single day of school so far. Keiko enrolls in remedial classes and struggles socially due to her reticent nature, though she manages to make a new friend in Yayoi Tomioka. Keiko runs into Iyo and tries to connect with her, only to find that Iyo has completely reinvented herself and tries to avoid discussing her past.