Chiiko Ogawa is the young schoolgirl protagonist, small in stature and relentlessly chasing an older boy nicknamed Sally with a deep, unrequited crush. She declares herself his girlfriend despite his actual romantic involvement with another girl, Tonko.

Her world revolves around school, where she strategically pursues Sally, joining his clubs and aligning vacations just to be near him. Her efforts earn her friendship, but Sally treats her more like a mascot or little sister, firmly placing her in the "friend zone"—a constant source of emotional pain as she yearns for more.

Over the course of a year, from spring to spring, Chiiko experiences the soaring joys and agonizing lows of adolescent first love. She wrestles with the awareness that Sally, though kind, offers no romantic encouragement, leading to many socially awkward stumbles fueled by her pursuit of the much taller, older boy.

Her interactions extend beyond Sally. She's friends with Tonko—who actually dates Sally—and Tonko surprisingly encourages and aids Chiiko's quest, all while navigating her own relationship with Sally's friend Yamashita. This creates a tangled web of youthful connections. Her parents—her father an English teacher—classmates, and teachers form a supporting cast, contributing to the narrative's comedic slice-of-life feel.

The story follows Chiiko's emotional journey across four seasons, charting her growth as she navigates the trials of one-sided affection during this formative year.