The Demon King is Reincarnated with a Hero System

*Editing*
[A chill psychopath exploring the cultivation world with scientific eyes]

Yuan Haoran committed countless evil deeds while in the modern world, and his life ended in a fiery (self-made) explosion.
When he is reborn in a world of magic and cultivation, Haoran intends to continue as a 'demon king' and live a free life without rules.
But his dreams are cut short when he is bound to the Hero System.
He agrees to take on the missions under coercion. But he is still a villain with a mind darker and more vicious than the cultivation world knows.
So, when Master Yuan helps people, chaos reign.
********
Later on:
"How can you accuse Master Yuan of using blood magic? He helped me get rid of the excess energy from the Scarlet Fire Fruit."
"Master Yuan has not turned our Black Mist Clan into puppets. He is using an advanced method to teach us new martial arts techniques."
"Doctor Yuan has not implanted Gu into us. He helped us deal with dangerous diseases and poisons, freeing us from a life worse than death."

Author's Note:
This is not a hot-blooded hero's journey.
Like Mads Mikkelsen's Hannibal, he is a super cool guy who likes learning and kills people sometimes.
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