The God of Underworld - Chapter 83 - 37:

The consciousness of a Great Magus suddenly returned to his original body on earth, just before he transmigrated into the magic world.

Nothing has changed, it's still the same earth.

However, when he looked at earth once more as a former great magus, he discovered earth was not as simple as he knew it to be.

Hidden magus, legendary races such as vampires and werewolves, they do exist, ruling the world through the shadows.

Faced with a former great magus, who possessed as many spells as libraries, would the earth that had been ruled by a few people be able to remain calm?

After seeking pleasure in the nightclub and a night of romance, he discovered there’s a seed in his stomach;

Masterpieces such as 'The Divine Comedy', 'The Theory of Evolution', 'Encyclopaedia Britannica', 'The Theory of Relativity'...Born in the history of human civilization, possess mysterious and magical powers in another world!Original sin, biological evolution, mastery of all arts...By reading the secret tomes, one can gain a variety of powers!The only trouble for the people of the other world is that they find it difficult to understand the texts from Earth.At this time, there comes a librarian from Earth...

She was a medical expert, talented and beautiful. She was reborn as his little wife. Her in-laws did not like her, her husband did not love her, and she was as timid as a mouse. She was weak and easy to bully.