Kyoukai Senjou no Horizon - Volume 8A, Chapter 8: Regretters on the Hill

A boy from 21st century Earth, met an accident and later was reborn in Naruto’s Ninja World.
He is born in Uchiha Family and becomes the useless brother of Itachi Uchiha and Sasuke Uchiha…. Let’s see how he changed the Naruto world.

- Description from Novelupdates

“Can you be useful to me?”

“I… I can be…”

The first time they met, she knelt trembling before him, begging for shelter. The slave caught his interest, and he brought her back to his palace.

She could’ve never imagined that in one night she’d go from a spoiled little slave princess of a defeated kingdom, to becoming a powerful prince’s pet.

He kept her by his side… spoiled her, cared for her, loved her, and gave her meticulous care and high status. Whatever she wished… she could do so under his name.

But, she angered him and chose to run away. He captured her within a day.

“Don’t forget, my little dearest, everything I have given you can be taken back…”

In a spur of anger, she hit him, her feeble hands striking against the flesh of his cheek. Gnashing her teeth in anger, she said, “Do you have the ability to take my child back?!”

- Description from Novelupdates

Kazuki’s life was painfully average—just another cog in the nine-to-five grind. His only escape? Binge-reading novels and no-lifing video games.Then he woke up inside one of those novels.Armed with unstable morals, unhinged humor, and a penchant for pettiness, Kazuki is determined to survive, thrive, and maybe cause a little chaos along the way.The world has no idea what’s coming.

On this land of real souls, with millions of different martial art institutions, there are so many strong fighters just like the trees in the forests.

Among all, a mediocre apprentice from one of the mediocre institutions suddenly became a martial art genius after a mysterious incident. Not only did he acquire a photographic memory and keen perception, but he had also come to discover that his ability to comprehend martial arts is astronomically good, which eventually made him an almost godly existence.

From the hot-blooded intense battles to the clashes between the top geniuses, Martial Arts is no longer limited to the mortal world, it reaches to a level that can do everything from controlling the oceans to flying up the sky and diving under the ground.

- Description from Novelupdates