The World of Otome Games is Tough For Mobs - Volume 8, Chapter 1 “Matchmaking”

What the hell? That menace who bullied me since I was six years old, actually became a pretty girl after three years of living apart? And she even ran to our agreed duel location to confess to me, hoping that I can become her boyfriend?!

This is a plot against me! There’s definitely an enormous conspiracy behind this! I won’t be fooled by you! Even if you tear up and act all pitiful, I will still disregard you and humiliate you, until you’ve have completely paid back all my childhood grievances!

What’cha lookin’at? There are very reasonable grounds for bullying a girl!

- Description from Novelupdates

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 the number one pill alchemist of the immortal world, Mu Chen had always believed that it was because he had single-mindedly focused on concocting pills that led to him to neglect disciplining his disciple. Which in turn, caused his disciple to be led astray by the seduction of devil cultivation, leading to the three realms to fall to disaster. After his rebirth, Mu Chen resolved to properly teach his disciple, give him the very best resources, earnestly love him, carry him close to his heart, teach him by way of example, and didn’t let him grow corrupt.