ONE: 하이스쿨 히어로즈

Lee Jung-ha

Kim Eui-gyeom

Kim Do-wan

Kang Yoon-ki

Kim Sang-ho

Kim Seok-tae

Kim Joo-ryoung

Myeong Da-bin

Shin Jun-seop

Nam Seung-Sik

Lee Chan-hyeong

Sung-Wook

Shin Jae-whi

Lee Ki-Yoon

임성균

Kim Seung-joon

육준서

Lee Geol-jae

Yoo Hee-je

Choi Ki-soo

İm Hyun-tae

Choi Hong-il

Hong Min-gi

Kim Nam-hyeop

Shin Hyun-soo

Kim Su Gyeom [Eui Gyeom's brother]

Ha Min

Kim Ui-gyeom Aunt (Eps 3)