Himari is a bright and innocent girl who missed most of middle school due to illness, and she enters high school overflowing with excitement for the sparkling青春 she has always dreamed of. When she is elected class representative alongside the serious and pragmatic Kageyama, she enthusiastically proposes planning recreational activities for the class, only to be shut down by him, who argues that they have no time to waste on games since the future is what matters. Kageyama is driven and focused on preparing for what lies ahead, while Himari lives in the present, craving every joyful moment she missed while she was sick. Despite their opposing worldviews, the two are forced to work together in their shared role, and through the small, everyday challenges of school life, they begin to understand each other. What starts as friction slowly deepens into mutual respect and affection, as each learns something vital from the other. The story follows their gentle, earnest journey from strangers who clash to classmates who quietly grow closer, set against the backdrop of a single transformative spring semester.