Choo Young Woo

Kim Jae-won

Moon Si-hwan

Troubled Student 2

Park Jae-hyeon

Troubled Student 1

Ryu Sun-gyu

Seo-yoon's father

Yoo Ah-reum

Jae-won's Mother

Yun Ki-chang

Math Teacher

Jang Yoo-sang

Korean Teacher

Lee Chae-kyung

Doctor

Jo Han-chul

Kim Seong-hyeon

Jin Ho-eun

Jeong Tae-hoon

Cho Yu-jung

Choi Ji-min

Shin Sia

Han Seo-yoon

Lee Seok-bin

Troubled Student 4