The manga follows Kei, a high school girl who refers to herself as incombustible because she cannot get excited about anything and has no desire to join a club. She spends her after-school hours exploring aimlessly on her way home. The story begins when Kei gets lost and meets Tsubasa, a girl who has just moved to town and knows no one. Tsubasa is passionate about playing basketball, and she invites Kei to start playing with her. The story is a four-panel coming-of-age narrative centered on how Tsubasas presence and enthusiasm begin to change Keis previously boring daily life. The setting is a high school environment where the after-school club activities take place. Tsubasa is a dedicated basketball player, while Kei is initially an uninterested observer who gets drawn into the sport. Notable narrative arcs include the initial meeting between the two girls, Kei reluctantly picking up a basketball for the first time, and the gradual shift in Keis personality as she moves from complete indifference toward discovering a new passion through her growing friendship with Tsubasa.