The Art of Chaotic Divinity - Chapter 1432: Refining the Dragon Fire

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

Protagonist travels between different anime worlds to right wrongs and uncover his reason for being along the way.

A world where magic beasts went extinct… until technology revived them!David wakes up in the middle of a Hatching Ceremony in the body of Jethro Merrick, clutching the lowest ranked egg.Now he’s living the life of a poor mechvet’s son, dreaming of adventure as a Riftwalker (think monster taming and dungeon clearing… but with cybernetic beasts!).But dreams crash fast. His egg hatches into a Red Lizard—cute but powerless and only used for pest control. Just as Jethro resigns himself to a boring life, a wrong turn during a Rift Training expedition lands him in a forbidden Rift zone.He barely escapes alive… only to wake up with a supercharged power: he can see the magic and mechanics of every mechbeast, right down to their origins!Here’s the catch: the ancient conqueror who once had this power wants it back, and he’s bringing an army of terrifying mechbeasts to take it.To survive, Jethro must build an army of his own, starting from his powerless frail lizard. But can a pest-control pet (and its rookie human) save the world?Let’s hope so, because our dear world of Nebulon desperately needs saving!

There are a total of seven sins, and a revelation is made to a young man named Alex that he is destined to become a demon lord, more especially a demon lord of sin called LUST.

It's not like he can change that and because he always knew something about himself was different—not in a physical sense, well, maybe a little—and not in a mental sense—but rather because he is thrown into a demonic war that compels him to accept his new reality.

He was only aware of a difference in himself. Relating to him and the ladies who are drawn to him... Well, it was more or less like he was a magnet in front of all the girls, and all the girls were drawn to him like a metal.