Omae wo Onii-chan ni Shite Yarouka!? - Volume 1, 15th of April, Monday

As Orson read the novel written by the girlfriend who had left him, he gently remarked on how terrible the story was. But then, noticing a foul smell coming from the kitchen, he went to investigate. He realized there was some kind of gas leak. Already furious about being dumped, Orson became even angrier at the state of his kitchen, and in his rage, he hit the light switch with a powerful punch. Naturally, the explosion that followed killed him instantly, and Orson passed into the afterlife.After spending some time in limbo, he found himself reincarnated in an unfamiliar world. However, he quickly realized he had been reborn inside the cliché-filled novel written by his ex-girlfriend. As if that wasn’t enough, he had ended up in the body of Neonidas, a useless duke who was also the fiancé of the story's villainess.____There may be a bit too much swearing and slang in the first chapters, but it gets less afterwards.There will be no yuri, bl or ntr in Neonidas(MC) harem

Though it may be a dream weathered, crumpled, fading,I held on without surrender.Through each repeated day, running toward tomorrow’s light,I became a knight, resolute and bright.

On the surface, he was striking and dashing, an object of envy and resentment from all men, but in secrecy, he was the formidable figure that made powerful leaders tremble. A marriage contract had brought him back to the city,In the bustling metropolis, a man fierce and enigmatic like a tiger, watch as he forged his own legend!

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