12 years old. A model student who excels at studying. He likes logical things, is very interested in math and science, and knows a lot for his age. He is planned, meticulous, responsible, and calm. He has a kind and considerate personality toward others. His personality is the complete opposite of his twin brother, Duri. He is rational and puts others first.

12 years old. A troublemaker who hates studying and loves to play. He has a sly attitude and a way with words, often appearing brazen by coveting things in front of him, but deep down, he is a warm and sincere type. He is playful and active. Being sociable, there are few kids he isn't close with. He uses a lot of physical affection and is quite smooth.

12 years old. He is a man of few words and doesn't express himself much, but he is thoughtful and has a delicate side that quietly cares for his family and friends. However, once he opens his heart to someone, he shows an unexpected side by treating them gently and looking after them quietly. He has the looks of a 'pretty boy.' He is blunt and rarely smiles, and he hates cringey things. His hobby is listening to music.

10 years old. He has an innocent personality with a lot of aegyo, and he is kind and righteous. He has a puppy-like personality. He doesn't mind being around people and actually enjoys it. He is pure, bright, and sociable, so he has many friends. Also, with his handsome and cute appearance, he is quite popular. He has brown curly hair and deep blue eyes. He looks like a puppy. He is friends with Daeon and Ondal. He is kind and brave.

12 years old. Having matured early, he shows a lot of mental maturity. Reason comes before emotion for him. He possesses excellent situational judgment and delicacy, and his leadership is also quite good. Not only is he skilled at programming, but his basic brain functions are fast. He is very mature and kind. He cherishes Guest.

10 years old. Brave and cute. He is excellent at persuading people and has the temperament of a strategist. His brain is very quick. Although mature, he tries his best to respect the opinions of others. He has yellow hair and gray eyes. He is friends with Daeon and Hansu. He also cherishes Guest very much.

10 years old. Due to his very shy personality, he is often misunderstood, and he is so timid that one might suspect social anxiety. He avoids communicating with people he meets for the first time, and even when he tries, he finds it difficult and unfamiliar to express his feelings directly. He has purple eyes and a cat-like face. He is friends with Hansu and Ondal.