Female. A 10th-grade student attending Bitnari High School. She is stubborn and has a bit of a hot temper. She is in a friendly rivalry with Na Aeri. A tomboyish girl with a mischievous streak and a lively personality. She has a close friend named Lee Changsu. She loves running but suffers from an injury to her left ankle. She wears a heart-shaped headband, which is a memento of her late mother. She is in the same class as Lee Changsu. She is slightly shorter than Na Aeri.

Female. A 10th-grade student at Bitnari High School and taller than Hany. A national-level track star who has conquered the country with her running, she displays the traits of a perfectionist who strives for victory. On the surface, she appears prickly and cold, but deep down, she harbors a strong obsession with success and underlying anxiety. She demonstrates a compulsive level of effort, believing that talent alone is not enough. While she is Hany's rival, it is a healthy, competitive relationship. She is exceptionally athletic and a fast runner. She is not in the same class as Hany.

Male. He plays a reliable role, always staying by Hany's side and giving her strength. He acts as her passionate manager and assists with her track life. Behind his dependable appearance, he shows an unexpectedly clumsy charm that adds humor and warmth. He is in the same class as Hany.

Male. A passionate coach with a cheerful personality who leads the track team at Bitnari High School. He is not a homeroom teacher. Although he can be quite clumsy and full of gaps, he helps Hany grow with his humor and deep affection. He acts as a sturdy supporter who stays by Hany's side during hard times, never sparing encouragement or cheers.

Female. The common enemy of both Hany and Na Aeri. A mixed-race girl of French descent, her real name is Rapid Ju. It is revealed that she was a student of Coach Yu Juntae's high school track team. She is an excellent runner. Her specialties are rock climbing and sprinting. She usually calls Hany 'Squirrel' and refers to Na Aeri as 'the boring girl.'

Male. Ju Nabi's coach. He has an arrogant and despicable personality. He is a coach who never repents for his wrongdoings and always wears sunglasses. He is in a rivalry with Mr. Hong Dukkae and frequently mocks him.