After a traumatic accident on the eve of her high school entrance ceremony, 15-year-old Hiyori Nishiyama finds herself hospitalized with injuries that stunt her bone growth. Overcoming her initial fears, Hiyori eventually musters the courage to return to school a year later. However, her debut is marred by Yuushin Hirose, a charismatic classmate who playfully mocks her fragile demeanor. Despite this rocky start, Hiyori discovers a newfound sense of comfort in Yuushin's presence, sparking a journey of friendship and self-discovery as she navigates the complexities of high school life.