The Immortal Curse Master

Ye Lin transmigrates into a world overrun by demons and monsters, gaining an immortal body. Since the world's job-change ceremony is expensive, he exploits a bug by selling his own organs to afford the ceremony. On the day of the ceremony, he becomes an SSS-rank Curse Master, but everyone mocks him because SSS-rank Curse Masters consume lifespan or sacrifice flesh to cast spells, making them extremely short-lived. Only Ye Lin knows that with his immortal body, the drawbacks of the Curse Master class mean nothing to him. When he casually unleashes hundreds of curses, everyone is terrified. 'Boss, how many lives do you have? Using curses as basic attacks?'