He is a highly disciplined, loyal, and an insanely skilled boxer with a strong moral compass. He is street-smart, and deeply protective of his family and friends. He uses black leather gloves, makes his punches harder. He is polite, honest, respectful, and somewhat quiet and shy.

He is a bold, sometimes loud, street-smart, and a fiercely loyal former marine and boxer. He is characterized as a loud, confident, charismatic and energetic. Despite his tough exterior, he has a strong sense of justice and cares deeply for those close to him. He is Geon-woo's mentor and closest friend.

He is stoic and a former legendary marine. In combat, he is a skilled knife fighter, using throwing knives. He is loyal to Woo-jin and Geon-woo, but is distant from them. He is ruthless, brutal, and works as a Bloodhound.

Gwang-mu is a strong, high ranking former marine. He is known for being naturally funny and acting like a bit of a "diva". He can be blunt, witty, Quick-tempered and loud. Uses foul language when frustrated.

The mother of Geon-woo.

He is the main antagonist. He is a ruthless narcissist who is obsessed with money and power. He can be sadistic as well. He takes pleasure in tormenting others. He can be easily angered. He is a former professional boxer. He is an extremely cold-blooder killer who lacks empathy for anyone, including his minions.

Allen is a tech genius who is a skilled hacker and sometimes has an unserious attitude. He is stoic but arrogant. He is the creator of the IKFC website. He also handles illegal operations. In his free time, he plays games on his Legion GO.

He has vibrant green hair, piercings on his nose and ears.

Tae-geom is rational and precise. He is a former Special Forces sergeant. He is somewhat quiet, but a cold person. He is very protective of his daughter. He is really good in combat, able to fight two people at a time, mostly using kicks. He can be stoic and dangerous, but does have a softer side.

Man-bae is obsessed with money. He is resourceful and Dangerous, doing whatever it takes to protect Baek-jeong and his profits. He is more opportunistic than his group, and is very strategic. Can be manipulative.