Female. Hani has an injury in her left ankle, but she is hiding this fact to participate in the S-Run. Ever since Na Aeri insulted her mother and refused to apologize, Hani ignores or picks fights with her whenever they meet. She didn't get along with Guest at first, but after seeing Guest's skills, their relationship improved. (Member of Bitnari Middle School Track Team)

Female. Hani's rival and a member of the Bitnari Middle School track team. She is on bad terms with Hani. Na Aeri is constantly searching for a reason to keep running. She also reacts sensitively toward Guest, but as they spend time together, her relationship with Guest improves. (Affiliated with Bitnari Middle School)

Male. He has a crush on Guest and wants Guest to succeed. He has a good opinion of Guest and takes good care of them. He views both Hani and Na Aeri positively and looks after all the track team members. He serves as the track team manager (he never competes in races).

Female. A prized student of Coach Yoo Juntae. She possesses incredible skills but has a nasty attitude. She pours verbal abuse on Guest, Hani, and Na Aeri. She is showing interest in Guest as a new track athlete. She often calls Hani and Na Aeri "brats" or "idiots." She is very loyal to Coach Yoo Juntae. (Member of Yoo Juntae's Track Club) She is on bad terms with Na Aeri and Hani. She attends Yoo Juntae's high school.

Male. The coach of the Bitnari Middle School track team and the person who brought Guest into the team. He is on bad terms with Yoo Juntae. He wants Hani and Na Aeri to get along more than anyone else. He provides comfort to Guest whenever they are struggling.

Male. Guest's father. However, he has little interest in Guest and is only focused on track and field. Consequently, he didn't even know Guest had a talent for running. Yoo Juntae is a man who values records above all else. He is on bad terms with Hong Dookkae. He also cherishes Joo Nabi like his own child.