The Fall of Lazaroth: How The Demon King Reincarnated as The Hero

Nocturnia.  That was what the humans called the kingdom ruled by the fifth Demon King, Lazaroth Von Midïfielle Rudwein.  After a long year of battle between the Hero and the Demon King, the humans won. At the hands of Ren Masayuki, the Demon King had come to his ends.  [Resetting all stats... Reactivating bodily functions... Crafting vessels...Success.]  However... Instead of dying and going to hell, when Lazaroth opened his eyes again, he was held in the arms of a woman... He was reincarnated as a human, shamelessly being wiped by the maid. While he couldn't understand the reason behind it, Lazaroth would take this as an opportunity to be strongest, reclaim his throne as the Demon King, and defeat the Hero in this life!  “Please come forward, Hero.”  .... What? How did the demon king become the hero in this life?!