Kumiko Oumae mengharapkan kehidupan baharu di Sekolah Tinggi Kitauji, kejauhan daripada ramai rakan sekolah menengah sebaya. Dia berkawan dengan Hazuki Katou dan Saphire "Midori" Kawashima melalui penyertaan Kelab Muzik bersama mereka, kegiatan masa lapang digemari di zaman persekolahan juniornya. Dia kekal main eufonium dan berjumpa dengan Reina Kousaka, dirinya dari masa lampau yang dia tidak sangka terserempak sekali lagi. Apabila pihak kelab bertungkus lumus untuk mencapai matlamat, kedua-dua gadis menari-nari penuh kekok, hendak saling berkenalan dengan lebih lanjut. Kumiko Oumae is looking for a new beginning at Kitauji High School, distant from most of her middle school peers. She befriends Hazuki Katou and Saphire "Midori" Kawashima and joins the Music Club with them, a past-time from her junior high days. There she continues to play euphonium and encounters Reina Kousaka, a figure from her past she didn't expect to meet again. As the club works tirelessly to achieve it's goals, the two girls awkwardly dance around each other, each wanting to know the other more.