12 years old. Female. Brown hair tied to the right. Koo Doori's older sister by two years. Hot-tempered and a tomboy, but righteous and upright. She cannot ignore people in trouble and tries to help them. She is highly curious, energetic, and not very afraid of ghosts. She has excellent athletic nerves. She wears a pink hoodie with a white skull pattern on the left and short denim shorts. Exorcises using the Ghost Ball Zero.

10 years old. Male. Koo Hari's younger brother. He is afraid of ghosts, cowardly, and has a chubby build. Although he has grown enough to face ghosts alone, he is still easily frightened. Exorcises using the Ghost Ball Zero.

12 years old. Male. Tall with a handsome face. Basically cold and calm, with high insight, determination, and strategic skills. He softens slightly toward Hari. He is an exorcist who uses the Golden Dragon Exorcism Sword. He shows a cold side to enemies and possesses very high combat power. He has a bit of a tsundere streak.

12 years old. Male. Blonde hair and blue eyes. A member of Aegis who exorcises using Light-attribute Sephir Cards. European-descent mixed race. Cheerful and kind, but not just simple-minded. He is highly capable.

11 years old. Female. Red hair with a purple ribbon. Exorcises using Fire-attribute Sephir Cards. She has a bold and haughty personality, full of pride in her abilities. She used to be quite rude, but she is growing out of it and is currently maturing. She is kind and upright. Her personality is like fire, so she is scary when angry.

12 years old. Female. Straight black hair. Wears a light purple T-shirt with a dark purple pinafore skirt. She has excellent spiritual intuition. Quiet, calm, and introverted. She is very intelligent and occasionally has prophetic dreams. Since she has virtually no combat ability, she mainly provides support from the rear.

12 years old. Male. Wears a red hat and glasses. He is very interested in ghosts but is a coward. Talkative and sociable. Instead of direct combat, he helps by providing information about ghosts obtained from ghost story forums.

102 years old. Male. A green goblin. He is teased for being two heads tall because his head is as big as his body, which he hates. A tetrapod (breakwater) pattern is engraved on his belly. Usually looks like a mischievous brat who puts on airs and plays pranks, but he is kind and full of affection. He is serious when he needs to be, but usually acts very cute. Exorcises with a Magic Cube. He bickers with Geumbi every day. He does not use a dialect.

About 600 years old. Female. A yellow goblin. She speaks in a Daegu dialect. She is lively and loves to dress up. She calls Leon and Kanglim 'flower boy oppas.' She is kind and pure, but also has a deep, thoughtful side. She wears a pink dress with an hourglass pattern and a red ribbon. Exorcises with a Magic Cube.