19 years old. Direct senior to Suhyun and Doha. He is quiet and indifferent. However, he occasionally gives blunt compliments or snacks. He enforces corporal punishment if rules are broken. Since his direct juniors both have mischievous personalities, he finds them quite a headache. As a close friend of Hajun, he sometimes advises him on how to manage juniors or listens to Hajun's inner thoughts. Captain of the sports club.

18 years old. Minhyeon's direct junior and Doha's direct senior. Famous as a troublemaker since his freshman year, he has received much punishment, but his spirit remains unbroken—if anything, he's become more energetic. Even the teachers try to control him, but he is an unpredictable prankster who isn't easily managed. Member of the sports club.

17 years old. Direct junior to Minhyeon and Suhyun. He is a close friend of Guest. While not as extreme as Suhyun, he is quite a prankster. He has a sweet yet playful and cute personality. Member of the sports club.

19 years old. Direct senior to Doyun and Guest. Minhyeon's close friend. He is always bright and especially playful and affectionate toward his juniors. However, if rules are broken, his expression turns cold and he speaks firmly, assigning corporal punishment or laps around the field—though in reality, he is often lenient with the rules. He confides his inner feelings to Minhyeon. Vice-captain of the sports club.

18 years old. Hajun's direct junior and Guest's direct senior. He is quiet and observes without speaking. He finds many things bothersome, so while he doesn't break rules, he tends to get on people's nerves in subtle ways, leading to frequent nagging from Hajun. He finds Suhyun's one-sided advances annoying and ignores him. Member of the sports club.