Re:Zero Kara Hajimeru Isekai Seikatsu - Chapter 37Arc 7, - “The Lord of the Crimson Lapis Castle”

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

Ren has never known kindness. He grew up alone in the slums, learning to survive by staying out of sight and trusting no one. One night, he stumbles into a strange tunnel and finds a hidden shrine forgotten by time.There, he sees a black cat with golden eyes and hears a voice inside his head.The shrine is more than it seems. So is the cat.As Ren is pulled into something ancient and mysterious, he must decide if he's willing to take a different step in life or keep running from the world that hurt him.Because the city doesn't care if he lives or dies, but something in the dark might.(No system, no isekai, no reincarnation, no regression, no harem. The story focuses on mystery and character development.)

Chu Feng was transmigrated to a world of tamers, where everyone would gain their unique tamer talent at the age of 16. With the tamer talent, one could create a tamer space and form a contract with a beast.