Sovereign of the Three Realms (WN) - Chapter 483: Rune of Heavenly Water, Prison of Water

Waking up, Kim Hajin finds himself in a familiar world but an unfamiliar body.

In this world, orphans or just anyone without any hope for this world can apply to become a “walking target”. Their sole purpose is to be a practicing dummy for the students of the sect who train to become “Demon Hunters”. These students need “walking targets” to test their training on living, walking beings of flesh and blood.
In exchange, they will be provided with food & shelter.
Their existence value is lower than a slave, but if they manage to survive a few years they can receive a life long pension.

Xiao Han is such a “walking target”. One time he witnessed a powerful Demon Hunter disposing a demon. When the demon died, a fragment of the demon that managed to escape entered Xiao Han’s heart. No one saw that, and even Xiao Han himself only felt some discomfort for an instant.

But that thing in his heart soon gave Xiao Han visions, and the first one is of a cultivation method which allows Xiao Han to absorb damage to enhance his body. A perfect cultivation method for a “walking target”.

- Description from Novelupdates

Noah Black, a young man with an abusive father who had no opportunities in life, condemned to live a substandard life because of his father's mistakes.

Noah Black from the parallel universe, a marginalized, obese young man with social problems and a somewhat problematic but loving family, but who couldn't live long because of the mistakes he made.

When Noah 1's mind enters Noah 2's body with a Gamer System, the path to becoming the biggest superstar in this new world begins.

Is that body fat? I work out with the system and in a few days I have the perfect body!

Is my family poor? With my knowledge of my other world, I can make easy money!

Is this face ugly? With System I can look beautiful without plastic surgery!

Do I sing badly? In a few days, the System will transform my voice into the voice of an angel.

Do I act badly? In a few days, the System will make me an Oscar-worthy actor.

I can learn anything I want!

“Rising to the top was like a game, and now I have become the Final Boss of the entire world!” -Noah Black.

Mission: Transmigrate world by world into a scoundrel’s body; clean up the original’s life.

Wei Mingyan is a liar, through and through. But he doesn’t see himself as such. His motto? “If one deceives others for a lifetime, then all lies would become the truth.”

- Description from Novelupdates