A twist of fate took the life of legendary hitman, Wu Qi. Strangely, he was not even aware of the identity of his killer. It was then that the Killing Intent System revealed itself to him. Wu Qi and the system made a pact— as long as he completes the tasks he was assigned with, he would get a chance at resurrection and uncover the truth behind his death. Just like that, Wu Qi, with the help of the Killing Intent System, travelled through time and space to put an end to enemies who are intent on killing others. Despite shouldering the burden of unpardonable sins, he decides to commit himself to saving the universe.

Original Webtoon

The legendary killer Wu Qi missed his hand and was killed by others. What is even more bizarre is that he doesn't even know who killed him. At this time, what appears in front of him is the existence of the killing system, and the killing system promises him: as long as the task entrusted is completed, the system soul "K" can help him to resurrect and tell him the truth of his death. This way, Wu Qi travels through various time and space with the help of the killing system to prevent enemies who are also dominated by killing intent.

Even if he is evil, meaning he doesn't forgive and doesn't forget, he still tries to save the world.
A killer who hunts other notable killers in another world, what could be more fun than this?