DxD: Fusion - Chapter 39: Kuroka

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.

He is the ruler of the mercenary realm, an overlord that gives headaches to the leaders of any country! For the sake of his friends, he’s willing to sacrifice himself; for the sake of his family, he does not hesitate to spill blood! He is a dragon, one that soars above even the highest of heavens. He’s a power that advances triumphantly through unstable situations, stirring up both the winds and the waters.

Suddenly a high school student Subaru Natsuki has been summoned to another world on the way back from the convenience store. With the biggest crisis of his life being summoned to another world and no sign of the one who summoned him things become worse when he is attacked.

More than ten years later, this sentence gradually spread in Elbaf Continent:

Never use magic to deal with tyrants, because you will find that he will return your spells to you thousands of times after being strengthened by countless magic specialties.

This is the story of a dragon-shaped self-propelled fort that keeps doing things in another world.

There is nothing that one magic can’t fix. If there is, then there are more. ——Izawa

- Description from novelbuddy