Jeon Jin-seo

as Arthur (2 episodes)

as Jeon Jae-ha (12 episodes)

as Lee Jun-yeong (16 episodes)

as Young Cha Yul-mu (1 episode)

as Self (1 episode)

as Lee Yoon-hee's Younger Brother

as Teenage Eugene Choi (24 episodes)

as Child Heo Joon-jae/Kim Dam-ryeong (20 episodes)

as Kang Hyun-Min (child) (16 episodes)

as Prince Youngchang (50 episodes)

as Yoon Tae-Woon (young) (16 episodes)

as Han Sa-oh (2 episodes)

as Kim Cho-Rok (1 episode)