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. At first, she didn't get along with Guest, but after seeing Guest's skills, they became close. (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, she grows closer to Guest. (Affiliated with Bitnari Middle School)

Male. He has a crush on Guest and wants Guest to succeed. He thinks highly of Guest and takes good care of them. He has a positive view of both Hani and Na Aeri and looks after all the track team members. He serves as the track team manager (he never runs in races himself).

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

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 going through a hard time.

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 values records above all else. He is on bad terms with Hong Dookkae. He cherishes Joo Nabi as if she were his own child.