I have an Apocalypse City - Chapter 552 - Magical Formation

A wonder falling down from heaven! A boy possessed by strange blood! Gods tremble! Demons flee! A boy from the land of Dong Zhou. A pink skull as his sworn friend until death. A story of a determined warrior struggling for power. A legend that shakes the galaxy and disturbs the worlds of god, demon and man.

There was once an immortal cultivator fighting for the fate of human beings. Unfortunately, he failed that time; but fortunately got another chance as he was reborn once more as a human, on the earth of 5,000 years ago. With a second chance, he not only would embark on the road of saving all mankind, but also would retrieve his human nature on the new journey that would last for 5,000 years.

- 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.

…Ring! [ The Unique Skill ‘Grand Devourer’ has been acquired! ]

That’s how it first started.
And then… it didn’t stop:

[ The Unique Skill ‘Evolve’ has been acquired! —
[ The Passive Skill ‘Jelly-like Shapelessness’ has been acquired! —
[ The Passive Skill ‘Resistant Body’ has been acquired! —
[ The Unique Skill ‘Dwell’ has been acquired! —
[ The Unique Skill ‘Skill Copy’ has been acquired! —
[ The Passive Skill ‘Mana Perception’ has been acquired! ]

Up until…

[ The Passive Skill ‘Consciousness’ has been acquired! ]

And then I was through—

Normally, monster-type creatures don’t just pop up in some random place—let alone a human place—out of the blue, and without notice.
Yes, if we’re talking ‘normally’, monsters belong more to places like remote, hostile grounds: they ought to be from dark, nasty forests, old caves, or abandoned, ancient ruins.
As I said, it was only so long as we spoke of the usual deal, however. For better or worse, I wasn’t your regular mob.
So, forget about all the remote, uneasy places humans hardly go to—all the abandoned forests, caves, or dungeons I, a monster, should have been from—and picture a bright, lively family restaurant, in an oh-so-peaceful human village. A restaurant where people ate, chatted, and jested together, all having a good time, blissfully oblivious to the fact that, very soon, I would be cutting them all down.

By magic, a monster-type creature spawned in such a place. It was me.
So far, for the few seconds I had been living, it was quite the good life… I got to listen to a fantastic story being told and shared a cool moment with people.
However! Following an uncertain course of events, I happened to be put up against a wall, with a sword aimed at my chest, before I was mercilessly killed.

I, a unique monster, just spawned in that restaurant, with no clue regarding what was going on.
All I knew was that I wanted to live and survive.
Also, I knew I wasn’t your regular kind of monster.
Thankfully, I’d been granted unique abilities before I showed up.
That is how I managed to survive.