Yukimi Yasuda shines as a star athlete in the Seishuu High School track club. She initially attended a different middle school, where she forms a crush on Katsuya Niimi after he sets national records in sprinting. At the beginning of the school year, she transfers to Seishuu High and actively pursues Katsuya, creating a source of annoyance and romantic tension for Yuri Nakao. As a third-year student, her romantic storyline finds resolution when she is paired with Jirou Yamanaka, the younger brother of Katsuya's former romantic rival, Kentarou Yamanaka. This occurs while the principal romantic relationships among the main characters solidify. Her pursuit of Katsuya and the resulting dynamic form a secondary romantic subplot within the broader narrative focused on interpersonal relationships and baseball.