Naruto System in One Piece - Chapter 64

A world where the [Demon King] was defeated by a [Hero] that came from another world. People carelessly forgot about their fear of the [Demon King] and of monsters, living in peace.

In a forgotten and run-down cave in the mountains, a new monster that should not have been born was given birth.

The monster’s name was the [Black Ooze]. It was nothing exceptional other than its black color, an ordinary slime.

However, this slime had the special characteristic of being able to take the abilities of the living things it swallowed. It preyed on an insect that had paralytic poison, as well as other animals. Following that, it attacked a human, obtaining his knowledge and [Desire].

Before long, the monster established its target as the female mage that came to explore the cave.

This world still wasn’t aware.

Charles or rather Xavier Dame was your average loner—broke, ignored, and invisible to the girls. But everything changes the day he awakens the [Harem Points System], a mysterious power that rewards him for physical and emotional interactions with women.From casual touches to heart-throbbing confessions, every action earns him points that can be exchanged for powerful skills, items, and stat boosts. Suddenly, he's not just charming—he's unstoppable.But things aren't that simple. The more hearts he wins, the more enemies he makes. From jealous rivals to yandere lovers and hidden organizations interested in his strange system, Ethan will need more than luck to survive his rise from zero to ultimate harem king.Can he keep his growing group of powerful beauties happy... and alive?

“What kind of guardian would you want to be? the one who destroys everything or the one who protects everything?”

Jason, one of the many casualties during a nuclear explosion gets the chance to reincarnate into another world due to his deeds during the war.

He gets tossed to another world due to ending up with the Shadow god as his patron, something deemed impossible.

With a system to guide him in the world of Clover and a family jinxed through the generations, his adventurous life in new world begin.

The hellhound is a legendary beast known for its fierce loyalty and formidable power, serving as a guardian of the underworld. During a cataclysmic cosmic conflict between gods and devils, the hellhound is tragically killed as collateral damage, his life extinguished in a battle far beyond his control.Millennia later, the hellhound is reincarnated as a human, awakening in a world that has forgotten his true nature. Retaining his past abilities, he must now attend a prestigious academy for those possessing supernatural powers, designed to train the next generation of guardians and warriors.As he navigates the complexities of human emotions and relationships, he must also confront the remnants of his past life. Whispers of the cosmic conflict still linger, and dark forces are at play, threatening to disrupt the fragile balance between realms. In a world where alliances are fragile and danger lurks around every corner, he must learn to embrace his identity as both a hellhound and a human.