Lu Yuan, 23 years old, was once the "Chosen Son" appointed by Heaven. He was endowed with the ninth level of Heaven's power and was willing to sacrifice his cultivation in order to protect the world. However, the law of heaven sent down a "heavenly punishment" when he was at his weakest, killing all the sect and relatives he protected just because he "disobeyed the destiny" and saved mortals who should have died in the disaster. In a pool of blood, Lu Yuan awakens the memory of the demon king in his previous life - he was originally the demon supreme "Yuan Emperor" thousands of years ago, and he sealed himself because he was tired of killing. After his rebirth, he appeared to be the most inconspicuous librarian of Imperial University. He was taciturn and always wore black shirts that were washed white, but in fact, there was a demonic energy sealed in his body that could tear the world apart. His character has changed from pity for the common people to cold and decisive, and his mantra has changed from "God has its own justice" to "If God is unfair, I will defy God." Growth arc: from a "hypocrite" who escapes the devil's nature, to a "judge" who faces up to his inner violence and uses the devil's ways to reshape a new order.
