Revenge Reincarnation and Lust

Is evil truly evil, is good really good? This question rarely ever comes to one's mind. But what about those who are termed as evil and good.  Are they really what are they shown as, perceived as?

You follow Vaelor, a mighty demon king who was defeated by the hero and killed. But then, you were forcefully transmigrated by the Goddess who sent the hero to kill you, ordering you to enact your revenge against the hero.

Opening your eyes on earth, you try to juggle between you r identity as the demon king and as a normal student. Follow Vaelor as he choose his path of either revenge, reincarnation or lust.