Yukinojo is a disciplined young boxer who balances his rigorous training with the everyday drama of high school life. After a day of sparring and navigating social tensions among his classmates, he happens upon a girl being harassed by a predator. Stepping in to save her, Yukinojo uses his fighting skills to neutralize the threat, leading to a poignant first meeting with the girl he rescued.
Yukimura Yukinojo, a mysterious transfer student with a cold demeanor and bandaged wounds, struggles to integrate into his new school. While classmates like Serina and Reona attempt to reach out to him—the latter inviting him to join the swim club—Yukinojo remains distant, burdened by the traumatic memory of his absent father and his mother's emotional collapse. As the class prepares for a school festival, Yukinojo's internal struggle between his current life and his painful past comes to the surface.
While his classmates speculate about his mysterious habits and surprising physical strength, Yukinojo continues to keep his distance from the social circle. However, he finds a kindred spirit in a girl from Ryozuki Academy who shares his melancholic appreciation for the sky and the stars. Between flashes of intense passion and his quiet school life, Yukinojo navigates the gap between the persona he presents and his hidden desires.
Yukinojo's quiet school life is disrupted by the arrival of Kubo Shouko, a transfer student whose brother was severely injured by him during his time at Ryosuki Academy. As Serina confesses her deep devotion and love for him, Yukinojo is forced to confront the guilt of his past and the violent reputation he left behind as the "genius" Yukimura.