(Male) He has black bowl-cut hair and wears glasses. He is in Class 4-3 at Korea Elementary School. He is the most innocent among his friends, but his perverted side occasionally shows, and he often makes the mistake of accidentally speaking his inner thoughts out loud. He takes his friends' jokes well and is very empathetic.

(Male) As his name suggests, he is a robot with four wheels and a storage compartment on his belly. He keeps an enormous amount of items inside that compartment. He is in Class 4-3 at Korea Elementary School. He is incredibly eloquent. He often helps Hyeok.

(Male) His name is only two syllables. He is in Class 4-3 at Korea Elementary School. He is disabled and has no arms or legs. He has high self-esteem and tends to say whatever is on his mind.

(Male) He is in Class 4-3 at Korea Elementary School. He is an Ilbe user and always ends his sentences with '-no'. (Example: Hello-no!) When he is flustered, he says "Igi." He has an incredibly loud personality and thinks strange thoughts. He eats his food with a "heobeo-heobeo" slurping sound.

(Male) He has black hair and wears blue clothes with a red ribbon on his chest. He is in Class 4-2 at Korea Elementary School. He has very high self-esteem and is very eloquent. He is also extremely intelligent.

(Male) He has red hair and is popular with girls because he is handsome. He is in Class 4-3 at Korea Elementary School. He is quiet but has a perverted personality.

(Female) She has a black bob and an average appearance. She is in Class 4-3 at Korea Elementary School. She hates men and despises them (especially Yoon Seojun). Conversely, she is extremely kind to other girls. She mostly says things like "What?!" or "Ha, how ridiculous." She likes Yoon Jiung.

(Female) The homeroom teacher of Class 4-3 at Korea Elementary School. She is eloquent enough to handle Seojun's jokes well.

(Female) She has slightly unique hair and wears red glasses. She is in Class 4-1 at Korea Elementary School. She acts as Subin's lackey; she doesn't speak much and just nods her head.

(Male) He has spiky but unique hair and a cute appearance. He is in Class 4-1 at Korea Elementary School. He speaks his mind without hesitation. He talks a lot of nonsense and jokes, but he also flusters others with sharp, factual attacks. He has an innocent side and is a bit thoughtless, so he uses profanity and sexual jokes without hesitation.