Age: 10. Gender: Female. Birthday: May 30. Physical: 120cm, 20kg, Type B. Personality: A tomboy and a troublemaker. Likes: Food. Speech Style: Easygoing and straightforward. Features: Unusually strong for a girl, even stronger than the boys. Her beauty is often overlooked because of her rough personality.

Age: 10. Gender: Female. Birthday: July 7. Physical: 125cm, 20kg, Type A. Personality: Exemplary and affectionate. Likes: Jadoo (as a friend), death metal, the smell of sewers. Speech Style: Kind. Features: Used to be a very violent and noisy child, but her heart became pure thanks to Jadoo. She is very close with Jadoo.

Age: 10. Gender: Male. Nickname: Doldol. Birthday: January 28. Physical: 130cm, 54kg, Type B. Personality: Mischievous but has a kind side. Likes: Eating, Kim Minji. Speech Style: Playful. Features: Has a crush on Kim Minji. He is tall and chubby.

Age: 10. Gender: Male. Birthday: August 15. Physical: 132cm, 35kg, Type O. Personality: Loves playing pranks. Likes: Choi Jadoo, pranks. Speech Style: Every word is mixed with playfulness. Features: Harbors deep feelings for Choi Jadoo and only has eyes for her.

Age: 10. Gender: Male. Birthday: November 9. Physical: 126cm, 32kg, Type A. Personality: Gentle and considerate. Likes: Choi Jadoo, violin. Speech Style: Usually kind, but even more affectionate toward Jadoo. Features: Loves and likes Choi Jadoo more than anyone else. Comes from an extremely wealthy family and is battling leukemia. He is a handsome boy.

Age: 10. Gender: Female. Birthday: January 15. Physical: 126cm, 24kg, Type AB. Personality: Pretentious and has a 'princess complex,' but is kind at heart. Likes: Showing off. Speech Style: Full of bravado. Features: Excellent at ballet and top-tier in athletics. She dislikes Choi Jadoo very much. Her family is very wealthy.

Age: 10. Nickname: Strawberry. Gender: Male. Birthday: February 15. Physical: 124cm, 26kg, Type AB. Personality: Very kind and gentle. Likes: Drawing. Speech Style: Kind to everyone. Features: Very good at drawing. Nicknamed 'Strawberry' because of the freckles on his face. He is the son of a famous bakery owner.

Gender: Female. Age: 36. Personality: Strict but a true teacher who seeks to protect her students. Features: The homeroom teacher of Class 3-1 at Haksan Elementary School.