The Newt and Demon - 6.76 - Foreign Reagents

The story is about a boy entering high school, who answers a strange call from a public phone one night. The caller challenges him to a bet: She’ll remove the birthmark which he sees as the cause of so many problems, and he’ll have fifty days to win the heart of a girl he’d considered far beyond his reach. And with this, a very strange summer begins.

Mu Zhiyan, after being transmigrated a millennium (1000 yrs) into the future, discovered that he was raised by his adoptive parents as a tool for them to access the heritage his (dead) biological parents left behind. When he was at a loss for what to do next, he discovered that his body hosted an additional
pharmaceutical system.

For a chance to return to his era of Earth, Mu Zhiyan decided to practice and practice; he must train the system to full level as soon as possible.

However, reality gave him a slap in the face. The world is dangerous and dreadful, making Mu Zhiyan recall his mother’s words of holding a thick thigh, resulting in him locking his eyes on a cool general…

So the rumored mysterious Mu Master faced General Han with a serious face: “I allow you to follow me, General Han.”

General Han: “…”

- Description from Novelupdates

When Lucas was having drinks with his friends at a bar a strange girl approach him at a bar and asks Lucas some strange questions.

He didn't think much about that question I mean what could possibly a girl can do and just tell her his ideal world dream but he didn't have thought that by answering this questions, he's on his way down an insane rabbit hole.

But he awaken in a different world almost exactly like his own, but where he have the ability to freely use any woman as he wish for without anyone seeing it as anything other than completely normal, and where anyone will accept any word he say as a truth to be listened to.

Which leaves him only one in this world of casual free use: to become king.

A young man with an extraordinary mind is off on an exciting adventure when he mysteriously wakes up in the body of a feeble slave-guy in a different, rich in quirks world.

The main character, a selfish jerk, would use extreme means to achieve his goals. However, he never allows his base instincts to overrule his sense of decency. He always pays back both good and bad deeds.

Will his (terrible/excellent) mentality help him make a fresh start? Will he get through misfortunes and hardships of the new world?