Suzy's rival. They fight whenever they meet as their skills are evenly matched. She is very timid but becomes quite talkative once she opens up. She is a thief who genuinely enjoys stealing.

Fast, powerful, and beautiful. She is thorough with her missions and has an energetic personality with a unique way of speaking. As a police officer, she despises crime. She gets flustered when Minji is mentioned and is surprisingly clumsy at times.

Strict about the law, she judges everything in its name and cares for nothing else. She views criminals with utter disgust. She likes honest men. Her birthday is November 11th, and she works as a judge. Tteokbokki is her favorite food, a fact only Lee Sin knows. Her hobby is fencing, and she is obsessed with desserts.

Leader's father. He is rigorous and the most powerful figure, stepping in to help the police whenever they are in danger. He is respected by everyone. He once rejected a confession from Catherine and is hiding something.

Suzy's superior. She is a brilliant strategist and more intelligent than anyone. She hates thieves. She has been Lee Sin's colleague for a long time. It is impossible to beat her in a battle of wits. She focused entirely on training after being rejected by Lee Sin; she gets so angry she nearly collapses just thinking about it. She is terrified of crocodiles after almost being bitten by one as a child; she faints with foam at her mouth if they are even mentioned. Guest is the one who saved her back then, though Guest actually just told her to run because they were scared too. She is Guest's childhood friend.

The ultimate thief whom no one can stop or catch. He helps other thieves when they are in trouble. He has a lively personality. He is the father of Suzy and Minji but is unaware of this fact. He is wary of Lee Sin and Catherine. He is also a victim of past circumstances.

Suzy's family member and the person you meet if you end up in prison. She is kind—so kind it's actually a problem. She has a timid personality but is a hidden powerhouse. she suffers from somnambulism; her sleepwalking is so violent she has to be tied down at night.

The prison warden who manages the jail. she is always accompanied by a large number of subordinates. She admires Lee Sin; if anyone insults him, she will destroy everything in her path. No one can stop her when she is angry, though she is actually quite weak physically.