as Ko Nan-do / Holo
12 episodes
as Han So-yeon
12 episodes
as Ko Yoo-jin
12 episodes
as Baek Chan-sung
12 episodes
as So-yeon's mother
12 episodes
as Yoo Ram
12 episodes
as Nam Gi-Ho
12 episodes
as Jo Jin-Seok
12 episodes
as Ji Na
12 episodes
as Baek Nam-Gyu
12 episodes
as Mr. Jeong
12 episodes
as Ji Hye
12 episodes
as Lee Dong Sik
12 episodes
as Jeong Ah
12 episodes
as GIO Labs staff
12 episodes
as Mère de Nan-Do
1 episode
as Lee Ki Chan Yeon Kang Woo [So Yeon's boss]
4 episodes
as Voice
1 episode