Kim Soo-ro

Character: Cheon Seong-geun

Park Bo-young

Character: Han Song-i

Lee Chan-ho

Character: Ok Gi-ho

Kim Hyeong-beom

Character: Cha Seung-ryong

Kim Ki-bang

Character: Meok-tong

Park Jin-Taek

Character: Jin-gook

Kim Yeong-ok

Character: Seong-geun's Mother

Ha Jung-woo

Character: Doctor

Jang Hee-Su

Character: Gi-ho's Mother

Lee Yong-i

Character: Eun-sil's Mother

Lee Hyung-Kwon

Character: Vice-principal

Gong Ho-seok

Character: Teacher Choi

Lee Han-wi

Character: Principal

Kim Sung-ryung

Character: President Lee

Moon Chae-won

Character: Lee Eun-sil

Lee Min-ho

Character: Oh Sang-hoon

Baek Sung-hyun

Character: Baek Jung-goo

Lee Eon-jeong

Character: Chemistry Teacher

Kim Byeong-ok

Character: Publishing Company President

Kim Won-jin

Character: Referee

Ji Hye-in

Character: Ji Yeon

Son Min-ji

Character: Interview Student 3

Oh Soon-tae

Character: Ja Ba Nom

Im Joo-hyeon

Character: Touchy Couple Male

Yoo Mil

Character: Touchy Couple Female