Lee Sang-hoon
Im Deok-gyu
Sin Jae-seok
Hong Kyu-min
Choi Joong-man (Turtle)
Head of Sadang High School students
Young Im Deok-gyoo
Pro athlete Jeong Sang-ho
Son Jin-Ho (Young)
Seoul Action School (Past)
Announcer
Director Jo
Various (voice)
Lim Soo-bin
Son Jin-ho
Mother-in-law