Toki Kanade is a troublemaking delinquent high schooler. After yet another fight with other delinquents, he's sternly reprimanded by the vice principal. Unexpectedly, gym teacher Kazuro Sahara intervenes. When Kanade asks why Sahara stood up for him, Sahara replies, “Fighting’s wrong, but it’s also wrong to scold someone without hearing them out.” Touched, Kanade decides to return to school regularly—just to see Sahara again. Thus begins a clumsy and heart-fluttering romantic comedy between a PE teacher and a delinquent student.

Thanks to Sahara’s influence, Kanade begins attending school and even makes some friends. But his grades are still poor—except in health and PE, which Sahara teaches. With the sports festival approaching, Kanade volunteers for the “borrowed item race” to get Sahara’s attention. But one of the prompts is “someone you like,” and participants must confess their feelings if they draw that slip…

After the festival, Kanade finds a scrapbook about Sahara’s past as a national-level swimmer and Olympic hopeful. Curious, he asks Sahara about it, but Sahara suddenly grows cold. Meanwhile, Kanade learns a secret about the Todo brothers, and Sahara, sensing the inner struggle of the elder brother Shinji (Daiki Matsumoto), begins to reveal his own emotional history.

To keep Shinji from competing in basketball while injured, Kanade headbutts him to force a break. In the nurse's office, Shinji reunites with his stepbrother Takuya. Meanwhile, Sahara takes Kanade to a lakeside and opens up about his past, revealing deeper feelings for Kanade in a moment of quiet honesty.

It’s time for the school cultural festival, and Kanade’s class decides on an all-boys performance of Snow White. Much to his dismay, Kanade lands the lead role—complete with a kissing scene. When his scene partner falls ill right before the show, a surprising replacement steps in: Sahara-sensei.

As his second year nears its end, Kanade begins to worry about his uncertain future while his peers pursue clear goals. A new teacher, Minato Nekoto (Kaito Hori), joins the school and turns out to be Sahara’s former swimming junior. But the tension between them hints at a complicated history.

Minato unexpectedly confesses to Sahara. In high school, Minato had turned down Sahara’s feelings, fearing he’d be a burden. Even after graduation, he continued caring for Sahara from afar, especially after Sahara suffered a university injury. Sahara is shaken by the resurfaced feelings and unresolved past.

Kanade shows up to school injured, having held back in a fight with another school’s delinquents out of respect for Sahara’s wishes. But when they show up again, he prepares to face them alone—at the riverside, a place full of memories for both Kanade and Sahara. In this emotional final episode, the bond between teacher and student deepens in an unforgettable way.