Park Hae-joon

as Miyoshi

as Jang Pil-wu

as Jung Byeong-su

as Moon Tae-seon

as Hwang Jin-man (12 episodes)

as Kyung-rok's Father

as Hwang Chi-seong

as Jang Junik (9 episodes)

as Lee Jae-geon (6 episodes)

as Ryu Jung-seok (12 episodes)

as Oh Sang-jae

as Yang Gwan-sik (middle-aged) (16 episodes)

as Self (2 episodes)

as Tae-seok / 6F (8 episodes)

as Self (2 episodes)

as Roh Tae-geon

as Park Seon-chang

as Doctor at School Infirmary

as Park Tae-soo

as Mr. Yoon

as Ahn Gi-chul

as Nam Geum-pil (12 episodes)

as Kim Ho-tae