Kanako Yūki is a student whose significant heart condition has caused her to fall behind two years academically, profoundly impacting her daily life. Despite her physical vulnerability, she possesses a distinctly willful nature. Her story pivots on a chance meeting with Masaki Takatō, a delinquent whose own path was altered when transferring to a school lacking the facilities to support his former basketball aspirations. This encounter sparks an inexplicable connection between them, becoming a catalyst for change in Masaki's life and drawing them into a developing relationship.

Navigating the social and personal challenges of her chronic health issue within the school environment forms part of her background. The core of her narrative arc lies in the evolving dynamic with Masaki, exploring how their bond influences both characters against a backdrop of external pressures and personal struggles.