Reincarnation of Nikola Tesla in another world - Chapter 1: Prologue

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

My handsome, overpowered dad, who only ever cared about me, ate something strange and turned into the Demon King. He used to be the sweetest, most doting father, but now he’s the final boss?! Because of this, my dad is fated to be killed by the male lead, and I’m destined to die lonely while mourning him. At that moment, I returned to the past and realized that this world is actually a game! I couldn’t prevent my dad’s descent into darkness, but no matter what, I must turn him back into his original self. If I succeed, I can get my loving dad back, right? For now, I need to get close to the male lead, who’s destined to kill my father…! So, I became a Holy Knight and even managed to be adopted as the ward of the Pluto Ducal House—the male lead’s family. …The problem is, I’ve become way too strong. As long as I get along with the male lead, my dad might avoid being labeled as the Demon King. “But that’s strange.” “…What is?” “Your lips… they’re heart-shaped.” “W-what? Don’t look at my lips!” At that, the male lead tried to avoid my hand and ended up rolling under the bed. “Ahhh!” “…?” He’s supposed to be the strongest person who’ll one day kill my dad, but for now, the male lead is just too cute.

In the back of the forest lives Allen, the antisocial wizard. He is feared by the people around him and called the “Demon Lord”.One day, while living out his life as a hermit, he finds a young girl named Charlotte who collapsed. Although innocent, she was accused of evil wrongdoings, had her engagement broken and was forced to flee her country.Upon hearing that, Allen recalled the bitter experience of being betrayed by a party he once believed to be his companions. Hearing the story of the 17 year old’s exploitation, Allen decides, “I’ll let her live in my mansion, and I’ll teach her all sorts of bad things…”

After transmigrating into a SF (Science Fiction) novel and enduring cruel hardships, I ascended to the throne as the Emperor of the Galactic Empire.[Welcome to the Integrated Dimensional Community.]As the community’s Lone SF Transmigrator, I unleashed the poison of new cultures on the uncivilized primitives of the Otherworlds.-Let there be light. To judge the horde of evil, the Apostle of the Goddess sent down a Graviton Surge. Thus, in that place was light along with a massive explosion…-The Grand Duke of the North has shown great interest in your Heattech…-I, as a Namgung, am thankful for the grace akin to the vast sea provided by the Great Hero. By virtue of the Vibroblade bestowed by the Great Hero, the nefarious Demonic Cult has…It seems like these Otherworlders can’t get their sh*t together.