Lord of the Sky City - Chapter 13 - 12 Great Invention?

Arakawa Kouki is reincarnated to a Japan with a different history than the Japan he knows with the memories of his previous life still intact. Kouki was discouraged, “Aren’t reincarnation stories supposed to be at some fantasy world filled with swords, magic and elves?!”

When I was reborn in South Korea, I wanted to live my life in peace. Pass the activation system, unlock the 'Big Brother' career, obtain the invincible system, and embark on the road to power

Gu Nianzhi had no idea how to get the aloof and handsome Major General to fall in love with her.

His eyes were dark and serious. “…Seduce me. If you can do it, I’m yours.”

Gu Nianzhi: “!!!”

- Description from Novelupdates

After getting shot, Lucas, a serial killer, reincarnated into the novel world as a tragic villain with the same name, Lucas Ciffer.

Lucas Ciffer was supposed to be the Holy Kingdom's successor to the throne, but his demonic appearance and the powers he possessed terrified the entire kingdom. A white-haired boy with red eyes and pale skin, together with his dark powers, got persecuted and exiled by his own family. Not to mention that in the future he was destined to die by the hand of the hero.

Lucas fell from holiness, and, with the serial killer's bloodlust and knowledge of the future, he decided to prove the world right.

Yes. I could be a villain; no, in fact, I WILL BE THE VILLAIN.