Classroom of the Elite (LN) - Vol 17 Chapter 3.3: Chapter 3 Part 3

A world-famous hacker and daughter of the most powerful criminal family who ruled the international underworld for many generations is killed when their organization is annihilated in a single night.

Damien Julian is an 18-year-old loser, who has been bullied and mistreated his entire life, at home, he has to deal with his abusive father, and at school, he is constantly been bullied by delinquents, and to make things worse he is always looked down upon by his peers, till one day a mysterious screen appear before him as it said.

[The world has seen the lingering evil in your heart]

[Would you like to be one of the nine demon kings of this world]

[If so what are you willing to sacrifice?]

In the heat of the moment, Damien made a deal with the world, that he would give up everything he owns, or do anything it wants, and in exchange, he shall be reborn as a new Demon King, and what the world required from him as payment was.

[In exchange for power, become a slave of the world, and act as an anti-body for all eternity]

At that moment, Damien agreed, but little did Damien know, that becoming a slave to the world meant he has to be its immune system, what that entail is, that anything that threaten the world must be destroyed even if he has to wipe out humanity, to save it, or assassinate historical figures to bring fort balance or even manipulating events that can potentially end the world, to save the world, this is the story of a necessary evil, not the story of a hero who cares for others.

As an ordinary human being on the earth, Tang Long was brought to the Cultivation World by a lost immortal, and relying on his amazing talent, he made it to one of the five emperors in that world. However, struck by Thunder of Nine Heavens, he lost his life. It was lucky for him to transmigrate in the human world in an intern who was named Qin Haodong. With his excellent medical skills, he became a divine doctor of traditional Chinese medicine and encountered the baby girl he made before going into the Cultivation World, whose mother was as pretty as a fairy. The little girl even asked him to find more lovers. What a cute girl…

Protagonist travels between different anime worlds to right wrongs and uncover his reason for being along the way.

- Description from Novelupdates