One Piece: Supreme Check-In System - Chapter 48: Voidreign Kingdom Appearance

An ordinary person who has passed through the Marvel World to gain the phagocyte ability and began to devour superpowers, and became the king of Marvel!

There are many female lords. The protagonist has gradually become the king of the Marvel world from ordinary people. The initial ability is the physique that changes through traversing. It can devour and stabilises without any side effects. The system is only an aid, you can also cross the plane!

- Description from Novelupdates

“If you intended to die anyway, don't die quietly like a pussy! Go out in a fucking blaze of glory!”That was the statement that changed my world forever.I was a loser in life. I died and got reincarnated into a Revenant. Revenants were people who defended the living from the dead. In exchange for a second life, they had one task and were blessed with one cheat ability.The task? To kick as much zombie ass as possible.Unfortunately, my cheat just made me “Rewind”. It didn't give me super strength, speed or the ability to fly. Hell, it didn't even give me a way to fight!Without any way to kill zombies, I nearly died on my first day on the job! Back then I remember crying and puking all over the place like a little bitch.But while I started out like a little bitch, I didn't stay one.Dying full of regrets changed me you see. So much so that I made a promise.I refused to repeat my mistakes when I was human. Reborn as a Revenant, I will never bow down to anyone ever again.Unfortunately, these Revenant bastards were old school. Like they hacked zombies with swords and all that crap old school. As a man born in the USA, I saw no reason why I needed to follow their outdated way of thinking.The modern world had the superpower of gun powder and lead. So instead of swords, I came after every zombie I saw with guns. Like countries in the middle east, I proceeded to blow the motherfuckers to kingdom come.And surprisingly because of “Rewind”, I found out I could never run out of ammunition.$200 for each kill. Hefty bonus for each area of hell liberated.What scared normal people shitless suddenly allowed me to earn millions every day. The richer I got the more “Freedom” I could unleash! Mortars, tank, air strikes to even nukes. Backed by modern science and technology, I slowly but surely drove the undead back.Along the way, I met and saved seven heavenly beauties. And all of them fell in love with me.They were a little obsessive, scratch that, they were all fucking insane. My precious harem was comprised of nothing but Yanderes in every sense of the word. Still, I would willingly burn the entire world for just one of them.For when I called, only my battle harem answered.And that was even before I learned of another secret.Exchanging bodily fluids with my girls gave me their cheats. Suddenly, in contrast to every Revenant in the world who only had one, I alone wielded eight. One from each girl plus my own.And so unfolded my 2nd life.Which eventually became my legend.Who am I you ask?I was born as John Smith.But these days not even my girls use that name.Both on Earth and in Hell everyone else just calls me Limitless.And I am the Strongest Revenant.

In a world where black holes, magical talents, and formidable hunters form the fabric of everyday life, Ethan Cross—a freshly graduated student with an uncertain future—once believed he would lead an ordinary existence like everyone else. However, everything changed when he awakened a seemingly feeble and inexplicable ability known as “Coexistence with Darkness.” No one took his talent seriously—until a catastrophic dimensional rupture unleashed terrifying creatures known as the “Demons of Corruption” upon him.On the brink of death, the pendant he had inherited from his father suddenly activated, summoning three dragon girls—beings of unimaginable power, yet with complex and rebellious personalities. Cursed in the past and trapped within that pendant, these three dragons have now become inexplicably bonded to Ethan. The twist, however, is that they neither recognize him as their master nor believe he is worthy of such a union.Now, Ethan must unravel the mystery of the darkness within him, learn to control his burgeoning powers, and find a way to tame these proud dragonesses—forces that could either aid him in his quest to conquer the underworld or lead to his ultimate downfall.A power that no one had believed in has become the key to mastering the shadows. Can Ethan harness it without being consumed by the darkness?

Ji Huan’s parents both died in a traffic accident.
Unexpectedly, his older sister also meets the same fate.
Yet everything starts when he says “goodbye” for the last time.

Hunting monsters? Genetic comparison?
Ji Huan flees with his older sister’s posthumous child to his hometown, Bade Town.
The three Grandpa, grandson, and nephew all live interdependent days.
However, inside the swaddling clothes is not a human baby,
But a monster…

Black egg body, white ring eyes, red mouth.
A child, ah! Doesn’t he have two eyes and a mouth! Resembling an egg, he is Ji Huan’s cute nephew!

Vermilion tiled wall, white lotus pond, convalescent courtyard.
This entirely neatly handsome and elegant young man: Ah Jin.
However, he told Ji Huan about the secrets of the monsters and discreetly taught him.
Bade Town is also slowly being covered in monsters…

Or, the record of a small countryside monster’s growth.

- Description from Novelupdates