He Became A Monstrous Genius After Obtaining A Time Dilation Artifact - Chapter 40. I have a permanent marker here, sign on my face.

Having trusted the goddess who promised my return to Earth, I joined the hero's party and defeated the Demon King.So when that promise was not fulfilled, it was only natural for me to desire my own fall into darkness.Harem | Fantasy | Sex | R18 | SMUT

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?

I’ve entered a hidden route in a failed game.And now, I have to become a false prophet.There’s no other choice.Since it’s come to this, I’ll become the greatest false prophet on the continent.

Being given a chance and reincarnated is nice and all, yet why do I have to become that male friend who just watches the protagonist flirting with his harem?---World: Kaguya-sama: Love Is War - Hyouka ----