Defiant Martial God - Chapter 53: The Demon Kills All

Roy’s life was nothing special. The only thing commendable was the last few moments when he saved a mother and her child from a drunk driver.
…
It’s really an egg! Damn it, what kind of monster have I become? Did I fall into Hell instead of making it to Heaven??
Join Roy as he ventures through various worlds with the Custom Made Demon King System—a system that allows Roy to draw anything he can imagine and create it through exchanging souls!

What would you do if you were to wake up one day to the message?

[You have 5 days until the next full moon]

[Your bloodlust is increasing]

Gary Dem is a person with a secret. While coming back to school appearing as a whole new person, he does everything he can to keep this from the people he cares about. For his path is one that led him to become part of the underworld.

The world has changed, and gangs rule the streets sponsoring big corporations. Bribing politicians behind the scenes and controlling the decisions people make without them knowing it. Using a new breed of humans called the Altered, a mixture of man and beast.

It was only meant to be a side job, he was never meant to dig in too deep, but on a mission for his gang, something went wrong, something changed him.

[You have 5 days until the next full moon]

[Your bloodlust is increasing]

The lone wolf… is about to go on a hunt!

After a god screws up and accidentally takes high schooler Shou’s life, he offers him reincarnation with a gift to make up for it. Shou asks to retain all his old memories for the new life. Shou is reborn as Will, a noble’s son in a world where magic use is common and involves knowledge of kanji characters. With all his memories, he’s a brilliant toddler, and when he experiments with magic, he finds that he has an amazing talent for it! What’s more, though he was smart but unloved in his old life, in his new life he has a mother and a father who both love him deeply. His future as Will is looking very bright and cool!

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates