The Genius Assassin Who Takes it All

Alternative:

The Genius Assassin Who Eats Everything / 혼자 다 해 먹는 천재 암살자 / Honja Da Hae Meongneun Cheonjae Amsalja

He is a successful writer who has created a fantasy world in his novel. But he made a terrible mistake in the end, causing the protagonist to reveal himself as a traitor and the world to be dominated by the demon king. He received the wrath of readers and regretted his choice.

Then he woke up in his novel, in the body of the villain Shin Kang Ho, a ruthless killer who works for the demon king. He is five years before the disastrous ending and has the chance to change the fate of the world. But Kang Ho has no intention of being a hero. He knows the world is cruel and full of greed. So he decides to use his talent and knowledge to achieve everything you can, without caring about others.

Kang Ho will devour all the resources, rewards, skills, and treasures he finds on his way. He will become the strongest and richest of all.