The Regressed Demon Lord is Kind - Chapter 556

Traveling through the world of Naruto, he is just a four-year-old boy who has no talent, no family, no blood, and no tailed beast.

Unexpectedly, after completing the Jain test, the system suddenly awakened.

Since then, he has drawn the glittering fruit, the shaking fruit, the dragon-killing magic crystal of fire, the magic eye of death, Geass, the blood of the ancestor giant, the eye of reincarnation, the eternal kaleidoscope writing wheel eye…

Also, Demon Sword Muramasa, Death Note, Longinus Spear, Godzilla, Zanpakutō*Kyoka Suizuki, Zanpakutō*River Blade, Natural Teeth…

- Description from novelbuddy

Year 2056, in a city in the Yuan Jiang Su Jin area. On top of a ruined, shattered six story residential apartment sits a teenager wearing a combat vest, militaristic trousers, and alloyed battle boots. On his back is a hexagonal shield and equipped is a blood-shadow battle knife. He sits there silently on the edge of the roof. At this time, the sparkling sky was shining and there was a refreshing breath within the air that blew towards him. However, there was only silence within the ruined, deserted city, with an occasional howl that makes your heart skip a beat.

A con-man and policewoman that are legends of their respective professions suddenly die, then are reincarnated and return to the Tang Dynasty of ancient China as little kids.

Accepting their second chance and forced restart, they choose to use the modern knowledge and specific talents that they have in their previous lives in order to live comfortably in this new life.

- Description from Novelupdates