Hidden Blade - Chapter 19 Really?

The protagonist of the collapse of the three former civilizations is Dr. Mei. What is the end of logic, the strongest brain, super intelligence, this is the story of the strongest scientist of Honkai with knowledge of the moon becoming the god of science!

- Description from novelbuddy

Growing up with eccentric materialist parents who left him in the care of his grandfather for a job overseas, Zhang Heng had learned to adapt and be unfettered by the oddities and challenges in life. But he would soon learn the baffling truth about the world he thought he knew when one day at midnight time froze and he found himself in a world so quiet and still it was deafening. That night, he discovered that he had 24 hours more than everybody else and thus, marked the beginning of his adventures. The mysteries surrounding his newfound ability only deepened when a strange old man claimed to have given Zhang Heng that ‘gift of time’ and recruited the young man to participate in a cryptic ‘life-changing’ game on his behalf. Little did Zhang Heng know that accepting those terms meant embroiling himself in many versions of reality and exposing himself to the hidden secrets of the world—a decision he could never undo.

An ordinary young man on earth, Xia Feng, traveled to a world of sword and magic, and took the body of Lucien Evans, another ordinary young man.

Yo, Hi! I’m Frank, I made a deal with a demon to pay me some money for receiving a guest for a few days every week.
I had no idea about what I have done.
On May 1st, Conan ‘the God of Death’ came to my house. I was forced to let him in and we get involved in a criminal case.
On May 8th, Bruce Wayne ‘Batman’ came to me. I was forced to follow him to fight crime.
On May 16th, Hannibal Lecter, The Silence of the Lambs, came to my home. I can only say that I really can’t stand my guests.

- Description from Novelupdates