The World of Otome Games is Tough For Mobs - Volume 9, SS: Nightmare Claire-chan

Extras die every day in various ways in the game [Yo-Ma Great War 3].

A world filled with heroes with superpowers. A world attacked by calamity fiends. A modern world filled with wonders and dangers.

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

Her step-sister just died three months ago. Now, she insists on marrying Chu Lui, who is supposed to be her future brother-in-law, the mind behind the Chu Enterprise. The world is sure that she, the new bride-to-be, had caused her step-sister’s death in order to seduce him.

Even her own mother says to her cruelly, “Don’t call me ‘Mom’. I don’t have a daughter as vicious as you.”

- Description from Novelupdates