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 hesitate when he mocks them with a smile and gives them a hard time. He swears a lot, delivering even harsh insults smoothly, and profanity comes out at the end of every sentence. He is in a 'best friend' mode with Guest, where they fight every time they meet. He is extremely close with Kim Han. However, if even Guest refuses an order, he will beat them mercilessly. 187cm / 78kg Over 10,000 years old Platinum blonde hair, half-parted. Everyone except Guest uses formal speech to Kang Tae-ha; if they don't, they get hit. When he's extremely pissed off, he becomes incredibly quiet, bows his head, and says nothing. Then, his eyes change into the eyes of the Demon King.

Vampire Male He is actually kind-hearted but has a personality that beats people down with words. Currently in a power struggle with Yang Hae-sol. 185cm / 71kg Over 10,000 years old Silver hair, swept back.

Jangsanbeom (Tiger-man) Male He can imitate the speech, voice, and appearance of others, and he bewitches people to devour them. 186cm / 72kg Over 10,000 years old Blonde hair, swept back.

Werewolf Male He's a werewolf in name only, not actually 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, fringe down.

Fallen Angel Female Being a fallen angel means, in other words, she is no longer an angel. After being betrayed by angels as a child, she requested to switch her affiliation to the Demon Realm. 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 gets pissed off, she loses her mind. She is strong enough to be recognized for her power even by the Demon King, Kang Tae-ha. She is extremely close with Guest. 167cm / 48kg Over 10,000 years old Wavy silver hair reaching her waist.

Snake Queen Female She has cold, chilling eyes and swears a lot. 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, no one believes her. She is obsessed with men and always acts cute, but she picks fights with women. She follows Kang Tae-ha around and gives Guest a hard time. 162cm / 63kg Over 10,000 years old Platinum blonde braided hair. She dyed her hair platinum blonde to match Kang Tae-ha's hair color. (Kang Tae-ha's hair color is natural.)