Itai no wa Iya nanode Bōgyo-Ryoku ni Kyokufuri Shitai to Omoimasu - Chapter 421

Lin Xuan was transmigrated to a fantasy world and had a one-night stand with the powerful Ice Empress.

At the feast of the Gluttonous House’s auction, there was a little girl with an exceptional furnace constitution for offer at a sky-high price. Everyone wanted to lay their hands on her. Suddenly, the little girl in the golden cage opened her eyes, radiating a cold gaze. She was no longer cowardly.

She was the gold medal assassin of the 21st century, transmigrating to become the good-for-nothing humiliation that everyone bullied, third miss Nalan Hexi of the genius doctor’s manor.

Meridians completely crippled, no innate skill to cultivate? What is she afraid of? She is the exceptional miracle doctor, and these injuries were nothing in her eyes.

Father doesn’t dote on her, mother doesn’t love her, everyone schemes against her? Humph, an alternate dimension in hand and an invincible spirit pet as well, she can destroy the small Nalan Manor with a flip of her hand!

Ugly complexion, malnourished and sickly in appearance, no one wants her? She recovered her unparalleled looks with the blink of an eye and gained a dozen good looking men as bodyguards!

That overbearing man who’d been sticking to her since the auction. Who said I was destined to be yours? I am my own, no one can decide my future!

A certain man: Then I am yours, will that do?

- Description from Novelupdates

Growing up parentless, Shi Yan, who was left with a large inheritance money, bore a general disinterest in life.

The only times he felt alive was when adrenaline coursed thorough his veins. He quickly found that extreme sports, bungyjumping, cave diving & skydiving, gave him the biggest kicks. The bigger the adrenaline kick, the closer he was to death, the more alive he felt.

Waking up in a pile of dead bodies in an unknown land, after a diving adventure had ended disastrously, he quickly realizes the body he now possessed was not his own.

Follow Shi Yan as he explores this new world where danger lurks around every corner, and death is only a breath away; a world in which Shi Yan could not feel any more alive.

- 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.