A Generation of Demon Kings Was Reborn as a Model of Righteousness?

A generation of demon king Fang Yi was framed by the demon sect and forced to be reborn and return to the past to become a decent person. He vowed to make the demon sect pay the price. Relying on the memory of when he was a demon king, he constantly broke the devil's plan for thousands of years in advance and became a model of righteousness. "Who is this kid? He is so terrifying. He can always destroy our plans." "Could this man be a spy who once worked undercover in our sect?" Don't think about it, I am a model of righteousness!