My Mr. Song is extremely protective ( Machine Translation ) - Chapter 2516 - Chapter 2596 -- Dawn's growth chapter 24

In the foreign world, the martial artists dominate the world and the sword of the emperor controls the fate of hundreds of millions of lives! Long Yu, the number one killer on Earth, after dying, takes rebirth in this new world in an aristocratic family of martial artists but faces rejection because he is unable to practice martial arts.

- Description from Novelupdates

Feng Ming was only 19 when he lost his life saving a child from death without hesitation. The grateful father of the rescued child grants Feng Ming a second chance at life. Unknown to Feng Ming, his soul has whisked away to a far away ancient land (resembling the dynasties of China).

The strongest Demon Lord dies, and reincarnates as a human. Not only that, he because of various incidents turns into the hero’s best friend.

Follow his journey as he tries to help the hero escape his fate, and on the sideline to conquer the continent while he’s at it.

After waking up in the body of the Young Master of the Luo family, he finds he has the knowledge of hundreds of games and Light Novels. However, he finds his Dantian is crippled, so he can’t practice cultivation! Luckily, he has the Upgrade system.