Demon Magic Emperor

Evil, bossy and relentless, he's an authentic demon king! He transmigrated into a ruthless housekeeper who is more merciless than the enemies! To steal the ancient demon emperor's power from him, the devil king, Zhuo Yifan, was betrayed by the people he once trusted. After reincarnation, he lost his powers and was haunted by his inner demons, which left him no choice but to be a butler of the young lady from a declining family. Downgraded from a devil king to a butler, how would he deal with this young lady and bring himself together with this declining family back to the pinnacle in this continent?