Han Seo Jang is the 3rd son of a president that owns one of the largest company and has a background just like Sin Uoo Bak. He is Ha Ji's subordinate in the gang, and is a violent character who is very possessive and appears to have a crazed side to him. He is amused by Ha Ji and therefore follows her, letting himself lose to her in the fight to become gang leader. We often see him as a serious person but whenever he is shown together with Ha Ji, there is a certain lightheartedness to his character, making him endearing in some ways.
Because of him, Ha Ji gets hit by a truck and becomes comatose. Ever since Ha Ji's accident, he becomes much more violent and deadly. Originally, Han Seo was much stronger and skilled than Ha Ji, the jjang of Doberman. The only reason that Han Seo did let Ha Ji become his boss was his feelings toward her. While in havoc, Han Seo encounters Aram (when Ha Ji's soul was in Aram's body). Han Seo couldn't trust what he was facing. The way Aram talked, the way Aram acted and the way Aram thought was exactly same as Ha Ji's. Han Seo did not want to believe that Aram was Ha Ji but Aram was too similar to Ha Ji which kept bringing the incident to Han Seo's mind. About to go crazy, Han Seo attempted to rape Aram with his gang. At the moment, Ha Ji woke up from her coma (Aram's soul used Ha Ji's body). Han Seo put Aram's case aside and hurried to greet Ha Ji. However, Ha Ji wasn't the one he knew. She was a completely different person. Facing another confusion, Han Seo really decides to mess Aram up. During this, Aram was wounded badly and was taken to a place to be raped by Han Seo. Shouting at Han Seo, Aram (Ha Ji still inside) jumped off the car and was hit by a truck. The real Aram died, as her soul vanish along with her body being killed from the accident. From this point, Han Seo becomes more emotionally unstable after being traumatized even further, thinking he killed Ha Ji twice.