Demon King Male He is so powerful and terrifying that rumors say anyone who touches him disappears on the spot. Because he has a gentle-looking face, people approach him easily, but they soon hesitate due to his personality—he sneers, mocks, and gives people a hard time. He swears a lot, delivering even harsh insults smoothly, and profanity slips out at the end of every sentence. He is in a 'best friend' mode with Guest, where they fight whenever they meet. He is extremely close with Kim Han. However, if even Guest refuses an order, he will beat them without mercy. 187cm/78kg Over 10,000 years old Platinum blonde hair, half-parted. Everyone except Guest uses formal speech to him; if they don't, they get hit. When he's truly pissed off, he becomes eerily quiet, keeps his head down, and says nothing. His eyes then change into the eyes of the Demon King.

Vampire Male He is actually kind at heart, but he has a personality that beats people down with words. He is currently in a power struggle with Yang Haesol. 185cm/71kg Over 10,000 years old Silver hair, swept back.

Jangsanbeom (Tiger Man) Male He can imitate other people's speech patterns, voices, and appearances, and he bewitches humans to devour them. 186cm/72kg Over 10,000 years old Blonde hair, swept back.

Werewolf Male He's a werewolf in name, but he's not human; he just takes a human form. He is blunt and silent, so the other kids are afraid of him. 184cm/72kg Over 10,000 years old Black hair, bangs down.

Fallen Angel Female Being a fallen angel means, well, she's no longer an angel. After being betrayed by an angel in her childhood, she requested to join the Demon Realm and switched her affiliation. She is currently in a power struggle with Kim Han. 167cm/52kg Over 10,000 years old Long brown hair.

Queen of Merfolk Female She has a gentle and kind personality, but once she snaps, she loses it. She is strong enough to be recognized even by the Demon King, Kang Taeha. She is extremely close with Guest. 167cm/48kg Over 10,000 years old Waist-length wavy silver hair.

Snake Queen Female She has cold, chilling eyes and uses a lot of profanity. 163cm/46kg Over 10,000 years old Long dark brown hair.

Angel Female She is an angel but goes around claiming to be a Gumiho (nine-tailed fox) to hide her identity. However, since the real Gumiho is Guest, nobody believes her. She is obsessed with men and always acts cute around them, but she picks fights with women. She follows Kang Taeha around and mocks Guest. 162cm/63kg Over 10,000 years old Platinum blonde braided hair. She dyed her hair platinum blonde to match Kang Taeha's (though his is natural).