MTL - Conan: I Am Not a Snake Spirit - Chapter 2421 you are right

Sixty Years ago, one middle aged man brought a Qilin that looked like a pug and a mandarin duck that looked exactly like a duck, walking into the Imperial City of the Central Plains for the first time.

Humanity lives under an unseen rule—the Ascension Cycle. A hidden system selects individuals at random, forcing them to complete tasks and gain different abilities as a reward. Anyone who fails a mission assigned by the system will instantly die on the spot.Ronan Vale wasn’t chosen at random.Killed on a mission gone wrong, he wakes up with a system unlike any other:[Evolution Path: Kill to Survive][Failure to Execute: Life Force Erosion Begins]Ronan has only one way to stay alive—which is to obey every mission assigned to him by the system. Unlike others, Ronan evolves after every task, each kill makes him stronger, sharper....but less human.As he fights to survive, he realizes his system is different. It evolves with him. It whispers to him. And it may not be just a tool—but a living thing.As war brews between Harbingers—those who embrace the system—and Eradicators, who seek to destroy it, Ronan is caught in the middle. But he has no time for their games.Because the real question isn’t how to survive.But what he’ll become in the process. A heartless monster bred only for destruction? he was about to find out.A:N; will there be romance? umm...NO!Harem? NeverKilling? YES!dark triller? YES!overpowered mc? hundred percent YES!

He Lang died by his own hands for the sake of his imperial younger brother’s ambition, whom he loved. He was offered to be reborn in exchange for giving up his past romantic feelings. Reborn without the burden of his romantic feelings, he brings with him a manual to new worlds. He wholeheartedly followed the instructions of the manual to complete the tasks, not knowing that the originally slag gong was blackening…
He pleaded to his affectionate Emperor brother to release him, he pleaded to the paranoid prisoner next door, but until the end he remained baffled.
In the end, he discovered that the full name of the manual was – “Slag Shou Cultivating Manual”
Σ (っ ° ° °;) っ!

- Description from Novelupdates

The entire Yunzhou knew that the Ye Family had a new step-child in the house: Ning Li, a low-born and barely literate. However, when she looked at her 17 years old self in the mirror after coming back to life, she grinned.At 17, her step-siblings had yet destroyed her looks and stolen her glory—she still had everything with her. Since she was given an opportunity to start over, she ought to take revenge on everyone who had wronged her before. It would be interesting.After Ning Li was chased out of the Ye Family, she was cherished by the most popular solo singer in the entertainment industry, protected by the top international racer, courted by the heir to a multimillion corporation, and loved by her billionaire grandfather who wanted her to inherit the family business.Even Second Master Lu said to her, “Hold up you little brat, I think you should come home with me.”Rumor had it that Second Master Lu was handsome and beyond any girl’s reach until that one fateful day, when someone saw a drawing of a cool and proud young boy with bangs covering his eyes fall out from Second Master Lu’s book.The news spread like wildfire overnight, and on the next day, Second Master Lu was questioned. Ning Li coincidentally passed by, and upon considering her relationship with him in her past life, she stepped in and shut down the busybodies.Lu Huaiyu stared at the girl before him as he subtly put away the love letter in his hands and said with a smile, “I shall repay you with my body for saving my life.”A long while later, Ning Li saw herself in that particular drawing and she was silenced. She knew it was all a huge mistake.