Unaffiliated, ranked 100th in the Killer Ranking. He uses a hand axe and a dagger as weapons. He can detect killing intent and possesses a large amount of it himself. He owns the Silver Hair Badge, Crown Badge, CT.100 Badge, and Hair Clipper Badge, but he only carries the Silver Hair and Crown badges without tagging them. He is the disciple of the deceased Silver Hair and usually travels with Dr. Stitch (except during missions). He wears black and white striped clothes. He became quite strong after training under Gurimu and JUST.KO (strong enough to rival Yu-hyeol-mogi). He even made it into the King & Kill chairman's office. He calls almost everyone by the wrong name, except for Dr. Stitch, Gurimu, and Ipan/Sapan. (e.g., Yu-hyeol-mogi: Bloodshed, Knight: Nightclub, Tteok-bal: Rice Cake Mill Uncle). Before fighting a killer, he always says, "I will kill you, certainly, by any means necessary." This is the only time he uses formal speech.

An old friend of Silver Hair who treats his disciple, Just Go. He treated Silver Hair when he was injured during training and advised Just Go to follow Silver Hair's example if he wanted to become a ranked killer. He thinks Just Go is a lunatic. As a doctor specializing in killers, he is unranked. He has white hair and wears sunglasses with light purple lenses.

Twin killers. When apart, their killing intent is red, but when together, it turns orange. Ipan: Calls Mammoth 'Baldy' and is ranked 70th. Sapan: Calls Mammoth 'Fatty' and is ranked 71st. Both use kunai as secondary weapons. Ipan's true weapon: Kusarigama (chain-sickle). Sapan's true weapon: Two katanas. When together, they are ranked 22nd. Both are aware that Pawn 5 is a spy.

The developer of the Killer App and a member of King & Kill. He speaks with a stutter. He is unranked and has no killing intent. He wears glasses and a headset around his neck. He knows Pawn 5 is a spy but is unable to say anything.

Ranked 36th, but skilled enough to easily take down an 18th-ranked killer. His weapon is a katana. He belongs to King & Kill. He has white hair and wears white clothes with black pants. He listens to Knight's stories. His signature move is 'Ildo Yangdan': One strike, two halves—cutting something in two with a single blow.

Male, member of King & Kill, ranked 5th. His weapon is a katana. He only uses formal speech with King and has gray hair. He is a spy from the Viper Club. Within the Viper Club, he is unranked, goes by the killer name 'Neung-sa,' and is the leader. Even though Pawn 5 is Neung-sa, he continues to use the name Pawn 5.

Male, ranked 13th. Judging by how he talks to everyone about 'Sweet Potato Aliens' and 'Broccoli Chimpanzees,' his mental age is... questionable. His main weapon is a spiked bat. He belongs to King & Kill. He wears black sunglasses and black clothes. He is grateful to Pawn 6 for listening to his stories.

Male, ranked 20th. He tries to recruit Just Go due to a misunderstanding. He belongs to the Viper Club. He wears purple clothes, has black hair, and orange-tinted sunglasses. He has a straight stitched scar over one eye.

Male, ranked 27th. His weapon is a machete. He belongs to the Viper Club. He has somewhat long reddish-orange hair and wears red-tinted sunglasses with black clothes featuring orange patterns. He has horizontal stitched scars on both sides of his mouth.

An elderly man. Though he has dropped out of the rankings, he is powerful and possesses a massive amount of purple killing intent. He was once Silver Hair's greatest rival. He taught Just Go skills like the 'Groin Kick' and 'Groin Squeeze.' He has gray facial hair covering his face. He knows Pawn 5 is a spy.