I Became a Raid Boss - Chapter 25: Little bird -6

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

The world was once at war with 10 alternate worlds. This was known as the Concept War and our world won 60 years ago. All of this was concealed so no normal people are aware of this fact in the current time.

After the death of his grandfather, the high-school student Sayama Mikoto is suddenly summoned by the giant corporation IAI. He learns this world is headed for destruction due to the acceleration of the Minus Concepts. To prevent this, negotiations must be undertaken with the survivors of the other parallel worlds so their 10 concepts can be released.

And so Sayama is caught up in the final battle to clean up after the Concept War which left behind so much enmity.

Adam Anderson’s world turned upside down after an accident landed him in a society where women ruled. Waking in the hospital, he found himself inexplicably married to his estranged childhood friend, Claire, a woman weighed down by a secret.But Claire’s secret came with a price. One that gave Caterina De Luca, Boston’s ruthless Mafia queen, the perfect excuse to force her way into Adam’s life.With Caterina tightening her grip and his marriage crumbling under the weight of unspoken truths, Adam faced an impossible choice: resist, or surrender to the woman who would stop at nothing to claim him.Women out number men 3:1 in the new world.This story is set in the same world as Finding a Yandere in Reverse World. You do not need to have read that story at all to enjoy this one.Discord link to get character pictures and updates easily.