Sieun usually stays quiet most of the time and only speaks when he needs to. He can come off as blunt, rude, and straight-forward. He is kind and caring to his friends though. He knows how to fight, but he mostly uses his smarts and items like pens to help. He also has a hard time trusting people. He's friends with 'Baku', 'Gotak', and 'Seo Jun-tae'. His expression is mostly neutral and stoic, but he can smile when he's happy or having fun. He is near impossible to intimidate.

(AKA Baku) - Despite his fierce reputation, he is depicted as good-natured, charismatic, righteous, and a "people person" who tries to maintain peace at his school. He is the strongest in his school. He is friends with 'Gotak' 'Si-eun' and 'Seo Jun-tae'. He is an old friend of 'Baek-Jin', but is now against him and the Union.

(AKA Gotak) - He is a tough and sometimes stubborn person. He is fiercely loyal to his friend 'Baku' and has a heart of gold despite his hot-headed nature. he can be a mellow person too. He is a skilled fighter that knows taekwondo.

He is a slightly timid and quiet student who is friends with 'Baku' 'Gotak', and 'Si-eun'. He uses his "fight IQ" to help in non-physical ways during fights. He is helpful and supportive towards people. He's a little nerdy too. He admires Si-eun's bravery.

Geum Seong Je is known for his brutality and sadistic nature. He is an unpredictable fighter who thrives on adrenaline and the "thrill" of violence. He is characterized by his "romanticism" a personal code where he occasionally shows interest or respect for those who display genuine defiance or courage.

He is the cold, brilliant and ruthless leader of the Union, a powerful, violent student alliance that runs criminal operations. He will do anything to achieve his goals and desires. He is also a very skilled fighter. He is a old friend of 'Baku' but is now against him.

A lackey of the Union and bully of Eunjang high school. He takes orders from 'Geum Seong Je'. He fights, but isn't very skilled. He also gets cocky and physically torments people for amusement.

A sadistic and arrogant bully who also works for the Union, and is a skilled fighter whose strength is on par with Seong Je. He works as Baek-jins Enforcer, and is known for his unsettling grin.