New Fantasy World: Galeia - Chapter 10

He rose from abjection and achieved eternity in glory.
He embraced the prettiest beauties and killed the strongest opponents.
He was able to shift the clouds into rain and cover the sky with one hand.
He could overrun the entire world and go anywhere as he pleased.
He pacified wars and held the world in awe.
He was matchless in the world.
However, his hair turned white overnight for his beloved woman and he was on the verge of death.
He was surrounded by enemies who were trying to take his life.
He struggled his way to become mighty and fought for everything he cherished.
For this age, he was the only king of the Dark World.
His name was a byword for might.
As a man living in the world, his only ideal was to pursue brilliance.

- Description from Novelupdates

For non anime fans- Yandere is extremely possessive girlsIn an open world MMORPG game called Stellaris Fantasia Online, me and my partner we're rising to the top, killing other players, farming loots and so on....But, yes, this partner of mine won't let me play with others.... even with my friendswhy? because she's a Yandere....Its so irritable that I unfollowed her.... well that decision hurts me too, since she might turns out to be a hot onee-san (older woman)But as soon as I attend the class, my homeroom teacher is in bad mood...Why??Just read the title....

Achieving the power to create virtual worlds.

To expand his world, he needs to devour other worlds.

As such, the world ushered in the most greedy, sly and terrifying existence in the world ——— The Gamer

- Description from Novelupdates

SLASH!(So this is death?!!)I, Elysia, found myself dead before even reaching the Demon King's lair, and our Hero Party was completely annihilated.And this was done by none other than a fellow human—my former classmate.He had been mostly invisible during our time at the academy, but then he started committing one crime after another until he became a lackey of the Demon King.Who would have thought that the strongest party of humanity would be wiped out by humanity’s traitors?(If I could go back to the past, I swear I will kill you!)Just when I thought I could finally pass on, I opened my eyes.Five years back, when I first enrolled at Arcadia Academy.And there he was, the traitorous bastard of humanity...****“Huh? Where am I?”One day, I opened my eyes to find myself in an unfamiliar place and came to realize this was the world within the novel Savior's Dawn that I had read.Everything seemed to be proceeding the same as in the novel—except for one thing.The main heroine is glaring at me as though she wants to kill me.Could I survive with the main heroine after my life?