Imperator: Resurrection of an Empire - Chapter 21: Provincial Cleanup (2)

This story is centered around the man named Yi Ji-Hyuk, who has spent 1000 years in a Medieval Western fantasy-like world before returning back to the modern-day Earth. When he returns, he finds that his home is facing monster threats, and that humans with superpowers have appeared to protect the innocent people of Earth.

“I miss the feudal era very much.” Chen Muyang once said to his friends.

When a friend asked him the reason, Chen Muyang said yearningly: “Because of polygamy in the feudal era, think about it, you can have many wives, you can sleep in different ways every day, and you can sleep together.”

“Cut!” The friends despised them, but their yearning was no less than that of Chen Muyang.

One day, the legendary system merged with Chen Muyang, giving him the ability to travel through the heavens and the world. Chen Muyang’s claws stretched out to countless goddesses in the heavens and the world!

“My, all beauties are mine!”

- Description from novelbuddy

The protagonist, Punk, is a cautious, cold-blooded, and ruthless Mage.

His goal is always his top priority, over feelings or morality. When unnecessary, he doesn’t like to act like pigs to eat tigers; there are almost no life and death struggles, sometimes risky but steady progress. No strong enemy everywhere, Instead, Punk is always a strong enemy of others.

And he has a very keen interest in the secrets and teachings of the Netheril civilization.

"When will people understand.... I'm only half insane?"