MTL - The Legend of Futian - Chapter 1 Here teenager

Hao Ren (literally means “good man”), as his Chinese name suggested, is a good man, and his ideal was to live a restful, comfortable life as a landlord. At least that was his plan before a couple of abnormal creatures rented his house.

Mira is determined to be a botanist—no matter how dangerous or violent it may become. Mira made two requests upon entering the multiverse: a botany class to further her research and to be dropped off in an isolated forest far from the violent god-rearing system BS going on. She was granted both—but not in the way she expected. The system abandoned her in a hellishly dangerous forest—where she earned a rare class that excelled at killing things.

You Liangxing would never open the speech function in game.
That was because his voice was…
Particularly! Kittenish!

But there was one day, he queued up with a teammate who had so much to say that they may as well explode. Vexed to the point of no return, he contributed a voice that was capable of splitting heaven and earth, “Don’t BB.”
The other party who was being scolded stilled. In the ensuing silence, he suddenly let out a long, relishing… Moan.
You Liangxing: “…..”

Later —
He realised that the person was a great god,
Much later,
Without him realising,
He became the great god’s royal healer.
…. And also his boyfriend.

- Description from Novelupdates

Chen Rui, an otaku from earth, is reborn into a human body in another world, who falls into the legendary evil, brutal world of the devil called Mozu where humans are treated as food. He has to survive while facing horrors of the devil, violent dragons and a variety of powerful enemies by depending on a strange super system chip and his wits. Surrounded by Devil’s beauties such as black-bellied lolita princess, cold queens, violent dragons, charming poisonous devils …

Wanting to live in the Devil’s world is hard! Wanting to live in the Devil’s world as a human is harder! Wanting a human to be the devil’s son-in-law is hardest!

Let us see how a small otaku uses power and strategy step by step starting from an ordinary human to writing a legend as the devil’s greatest son-in-law.