UNFORGIVABLE! Unpardonably Vicious!

Read manhua UNFORGIVABLE! Unpardonably Vicious!:

Wu Qi, the famed killer, lost his grip and was slain by someone else. Even stranger is the fact that he has no idea who killed him. At this moment, the killing system’s existence and its promises to him materialize in front of him. The system soul “K” can assist him in rising again and reveal the truth about his death, provided the duty assigned is finished. Wu Qi uses the killing system to travel across time and space in this manner in order to thwart opponents who share his desire to kill. Despite his terrible nature, Wu Qi is a man of forgiveness and forgetfulness, and he still makes an effort to rescue the planet. What could be more entertaining than a killer who pursues other well-known killers in a different world?