In my name, who is the murderer?

It’s Boss Cui.

The gang boss ending of "In My Name": He was killed by Zhiyou. Boss Cui was the real culprit who killed Zhiyou's father. Not only that, he also killed Zhiyou's beloved man. , Zhiyou hated Boss Cui very much, and finally she killed Boss Cui at all costs.

Boss Cui was originally a good friend of Zhiyou’s father, but later Boss Cui learned that Zhiyou’s father was a police undercover agent. Boss Cui felt that he had been deceived. He said that he hated betrayal the most, so Boss Cui was there. When Zhiyou's father went home to see his daughter, he killed Zhiyou's father in front of his house. Then Boss Cui deceived Zhiyou, saying that the police had killed her father, tricked Zhiyou into joining his organization, and even went to the police Bureau became an undercover agent and helped him do things.

Later, Ji-woo hesitated because of Detective Kim whether to continue on the path of revenge. Just when Ji-woo decided to let go of hatred and start a new life, Boss Cui appeared again and killed Detective Kim. Both her father and lover died in front of her. Zhiyou was devastated. She became even more furious when she found out that Boss Cui had killed her father. It turned out that Boss Cui had been using her for so long. In the end, Zhiyou went to Boss Cui alone. At his base camp, he used the skills he learned from Boss Cui to kill him with his own hands.