Supreme Dan Refiner of Realms - Chapter 1764 - : The Arrival of the Fire Emperor

[Warning! The MC here is the literal incarnation of evil and madness throughout the story.]Valtar Titanblood formerly known as Ethan Martin on Earth was struck by an unimaginable tragedy and took his own life at the end, his whole life filled with misery and incompetence of his own doing.Then he transmigrates to a world of infinite proportions and power that defies logic, this new world which is filled with Dragons, Titans, Ouroboros, and countless more bloodline creatures and mythical beings, also powerful humans who are known as Mystic roams here as well.Valtar in this new world has the Karma System and the bloodline of an unknown titan running through his veins, with these powers in hand he who was supposed to become the symbol of justice and equality decided to become the paragon of madness and evil.He who had the tools to become the Judge of Truth and the figure of Respect chose to become the arbiter of chaos and the embodiment of fear.

Raised as nothing more than a weapon, Xin Long was kidnapped and forged into a killer — his freedom severed, his name reduced to a whisper. In a world where trust is a death wish and mercy is a myth, he treads a path of blood and betrayal, outwitting ruthless foes and surviving inhuman trials. Yet, the deeper he delves into the shadows of Jianghu, the more he unravels a web of dark secrets that bind the martial world.Step into the dark side of Jianghu and witness the so-called Forgotten Tale — a story never meant to be told...

“If I don’t die… I swear I will act on all my evil thoughts..”

Not exactly everyone’s typical thought when they’re about to die. What will a cowardly young man do when reincarnated with the evil powers to redefine his destiny? Can the natural kindness of human nature triumph over evil? Will he become the cold-blooded demon king of legend, or will he forge his own path and rain down another kind of terror?

- Description from novelupdates

A girl who calls herself a demon appeared before a timid student named Fumio Kijima. The girl claims to be a campaign girl from the demon world and she gives him the ability to “summon a room” from nothing but thin air.

At first he doesn’t abuse his power and uses it as a convenient ability in his every day life. But one day he is bullied by his classmates under a false pretext and is made to suffer. In the past he would have wallowed in misery and cried himself to sleep, but now he had a power to call upon.

“I will make them regret it!”

Using his powers to summon his “room”, he begins his era of confinement and brainwashing to achieve his goals.