Kim Do-wan

as Park Seung-jae (5 episodes)

as Kim Hee-seung (1 episode)

as Kang Yoon-ki (8 episodes)

as Audition staff

as Lee Do-han (12 episodes)

as Gu Jeong-hoon (9 episodes)

as Upstairs Neighbor (1 episode)

as Han Joo-hyeok (12 episodes)

as Do Jae-jin (16 episodes)

as Kim Yong-san (16 episodes)

as Seo Tae-hwa (8 episodes)

as Kwak Sang-Pil (8 episodes)

as Han Sang Jin

as Chan-young

as Chan (12 episodes)

as Sang-sik

as Student

as Nam Ji-hoon (10 episodes)

as Ji Eun-woo (8 episodes)