설경구

Kang Ho-chang

천우희

Song Jung-wook

문소리

Gun-woo's mother

오달수

Do Ji-yeol

고창석

Teacher Jung

강신일

Principal

성유빈

Kang Han-gyeol

남기애

Gyu-beom's grandmother

이미은

E-den's mother

Yoo Jae-sang

Gun-woo