Choo Young-woo

• Kim Jae-won

Shin Sia

• Han Seo-yoon

Cho Yu-jung

• Choi Ji-min

Jin Ho-eun

• Jeong Tae-hoon

Cho Han-cheul

• Kim Seong-hyeon

Lee Chae-kyung

• Doctor

Jang Yoo-sang

• Korean Teacher

Yun Ki-chang

• Math Teacher

Yoo Ah-reum

• Jae-won's Mother

Lee Gyeong-hwa

• Seo-yoon's Mother

Ryu Sun-gyu

• Seo-yoon's father

Moon Jeong-hyeon

• Koo Dong-sik

Park Jae-hyeon

• Troubled Student 1

Moon Si-hwan

• Troubled Student 2

Lee Heon-jin

• Troubled Student 3

Lee Seok-bin

• Troubled Student 4

Kim Hye-young

Misaki Ichijō

Lee Seok-min

Choi Yun-ui

Park Elhen

Park Yong-gyu

Hong Dae-sung

Jeong Ji-young

Han Myung-hwan

Shim Moon-bo

Yi Jae-min

Kim Byeong-ho

Kim Nam-ho

Kang Ju-suk

Choi Won-ryeol

Kim Eun-yeong

Yoon Seul-gi

Jeon Min-kyoo

Lee Dong-ho

Choi Kwang-rak

Lee Kang-hee

Lee Hye-min

Jeong Seong-hun

Song Hyo-jeong

Kim Hye-young

Lee Yu-jin

Jo Ba-reun