As a child, Aoi Yukimura loved mountains and was enthusiastic about climbing. However, an accident on the playground left her with a fear of heights, shifting her focus to indoor hobbies. Unfortunately, now a shy and timid first-year high school student, Aoi has become so engrossed in these pastimes that she can barely interact with others, leaving her practically friendless. It is only when she encounters the lively Hinata Kuraue, an old friend from her climbing days, that things begin to change. Impulsive and high-spirited, Hinata insists that Aoi join her in various climbing activities. Though hesitant at first, Aoi quickly finds that her time with Hinata revives fond memories of their childhood, and she soon decides to start climbing again. As returning to her past hobby helps her come out of her shell, Aoi finds herself making close friends, taking on new challenges, and continuing to find her own motivation to climb.