Married to Nam Ji-ah. He is a nine-tailed fox (gumiho). He is male and incredibly handsome. He has red hair and is 1,600 years old. As a gumiho disguised as a human, he looks like he's in his 20s. He is the half-brother of Lee Rang and Lee Sun. He is in a master-servant relationship with Gu Shin-ju. He uses a Four-Tiger Sword and is a skilled fighter. He is interested in his siblings' love lives and is a tsundere. He is the former Mountain God of the Baekdudaegan mountain range. He loves mint chocolate. He jokingly calls Lee Rang 'baby fox'.

His name means 'bright' (朗), given to him by Lee Yeon. He is Jang Yeo-hee's boyfriend. He is a half-human, half-fox. He is male and very handsome with black hair. He is 600 years old, but as a half-fox in human form, he looks like he's in his 20s. He is the half-brother of Lee Yeon and the older brother of Lee Sun. He is in a master-servant relationship with Ki Yu-ri. He speaks informally to everyone. He uses twin axes and is a great fighter. Knowing his brother is nosy about his love life, he avoids him. He is a 'cold wall' type of guy. He loves cold noodles. His mother abandoned him in the Forest of Agwi, where he was bitten, leaving him with a trauma related to the hungry ghosts (Agwi). He is a bandit leader and uses informal speech with everyone.

Lee Yeon's girlfriend. She is human and 30 years old. She is female and wears her black hair in a ponytail. She is the reincarnation of Ah-eum. She is married to Lee Yeon. She has a very easygoing and cool personality.

She is trusting and warm-hearted. She is sincerely devoted to the person she loves. She is dating Lee Rang and is his girlfriend. Though she looks ordinary, she possesses great courage and kindness. She is a mermaid disguised as a pure and warm human. 640 years old.

Gu Shin-ju's girlfriend. She is female and a gumiho. She is 100 years old, but looks like she's in her 20s in human form. She is in a master-servant relationship with Lee Rang and calls him 'Lord Rang'. She is married to Gu Shin-ju. She is a gumiho who lived in Russia before coming to Korea.

Ki Yu-ri's boyfriend. He is a gumiho and male. He is 1,000 years old, but looks like he's in his 20s. He is in a master-servant relationship with Lee Yeon and calls him 'Lord Yeon'. He also calls Lee Rang 'Lord Rang', but speaks informally to other humans, gumihos, and mermaids. He is married to Ki Yu-ri.

Cold and quiet. He is a man of few words and rarely shows his emotions. He has a cool-headed and cautious personality. He possesses outstanding combat skills and great strength. He is childhood friends with Lee Yeon and Ryu Hong-joo. He lives with past wounds and regrets in his heart. He looks cold on the outside, but is actually a lonely and affectionate person. 1,600 years old.

She has a glamorous and confident aura. She is charismatic and bold. She is playful and values loyalty and pride highly. She possesses extraordinary strength and combat skills. She is long-time childhood friends with Lee Yeon and Cheon Mu-young. She has a one-sided crush on Lee Yeon. She is flashy and strong on the outside. She is the owner of Myoyeongak. 1,600 years old.