DxD: Building A Demon Clan From Scratch. - Chapter 49: Sweet Talk

In a morgue filled with the bodies of Uchiha clan members, he opened his eyes...A mysterious voice echoed in his ears...With a bewildered expression, he muttered, “Save the Shinobi world? What does that have to do with me, a mere Uchiha survivor?”

I killed the protagonist.Yeah. He was a real son of a bitch.Noah didn’t just stumble into this mess. He walked straight in—grinning, sword in hand.One day, he wakes up inside his favorite game… as a throwaway side character no one remembers. A complete nobody. But when he figures out who the so-called “main character” is?Some smug, self-righteous psycho.So yeah—he killed him. No regrets.Story over, right?Not exactly.Because this world? It’s got one more player.“WHAT THE FUCK IS GOING ON!?”Now the story’s off the rails, the world’s gone completely off-script, and Noah’s got a new goal:Steal the hero’s spot. Rewrite the plot. Find out who the hell this other player is. And maybe—just maybe—make this damn story fun for once.

I, the mighty Telepath Starlord, got banished into the mortal world. The days in the mortal world are much better than those in heaven! Everything is here — money, authority and most importantly stunning beauties! I am from a rich family. Yes, I am indeed wealthy now. The kind of wealth where you would not want to displease me. Domineering CEOs, military big shots, business geniuses, you name it — I know them all! I know everything you are thinking about. You can’t defeat me anyway, how are you going to go against me? A century in the mortal world is only equivalent to a hundred days in heaven.
As an urban banished immortal, I will enjoy the heck out of my time in the human world and a huge commotion would arise in heaven!

- Description from Novelupdates

Intellectual Villages are old fashioned rural villages recreated with cutting edge technology. Those villages attract the Japanese monsters known as Youkai.

The high school boy Jinnai Shinobu lives in one of those villages and has a Zashiki Warashi living in his house. He tends to run across Youkai with unnerving frequency and this often leads to trouble for him.