The Nice Guy

Lee Dong-wook

Park Seok Cheol

Lee Song-Kyoung

Kang Mi Yeong

Hye-young Ryu

Park Seok Hui

Na-ra Oh

Park Seok-gyeong

Park Hoon

Kang Tae-hoon

Ho-jin Chun

Seok Cheol's father

Kim Min-Gwi

Im Bok Cheon (Tae Hun's subordinate)

Park Mi-hyeon

Yoon Hye-sook

Tae-yu Moon

Jang Gi-hong

Park Sung-Yeon

Go Jeong-nim

Sung-Kyun Im

Jang-hak

Kim Young-mi

Staff of a study abroad school

Park Seo-Kyeong

Kang Mi-yeong (young)