America Tycoon: The Wolf of Showbiz - Chapter 51 - The Human and The Ghost

Ryuk’s life in the forsaken Grade E city was bleak, but it truly shattered when a Knull raid took his last family and left him for dead. On the brink of despair: [System Activation Complete.] [Congratulations, Host has awakened the Draconic Pets Evolution System!] [Welcome host, to the path of domination.] Thrust into Endearth, a shattered mirror of Earth teeming with mythical creatures—vampires, werewolves, cosmic gods—and the unstoppable Knulls, Ryuk sets out on a journey of relentless growth, vengeance, and discovery. But power comes with a price, and the dual nature of his gift could either save humanity or destroy everything. This is a story of evolution, redemption, and defiance. Join Ryuk as he rises from nothing, building unshakable bonds with allies and carving his path in a world where strength is the only currency.

Once upon a time, a hero had been summoned to a different world in order to defeat the demon king. After the war stretching 3 years ended the commendable hero slew the demon king. And he was forcibly deported back to earth after being dismissed.

Such bullshit!

Elves in addition to beast race, dwarfs and demon race. Even though I wanted to make a harem in the different world I saved! My dream will not come true on earth, where there is no magic at all. Thus, the hero returns on his own. Without the blunder of being extradited to earth this time, he will build a harem of his own in a different world.

Through a mysterious portal, Chen Jin arrived at this strange place – a post-apocalyptic world where civilization had been destroyed.

Consequently, he found –

A piece of metal scrap
A robot trash collector
A battleground
A city
A ton and more of gold
A copy of high-tech documents
A…
In short, Chen Jin found a planet.

- Description from Novelupdates

A boy awakens alone in the Fairy Tail world, lost and uncertain. As he ventures through this magical realm, he unravels the secrets of his mysterious new identity, unlocks hidden powers, and carves out his destiny in a land brimming with wonder, danger, and limitless adventure.“Check out my other work, Reincarnated as Ash: A Pokémon Tale.”