The Simple Life of Killing Demons - Chapter 68Book 12:

Memories shape who we are—they define us, anchoring us to our pasts. They are like videos, playing endlessly in our minds.But everything changed one day when people began to relive their memories. However, it wasn’t the pleasant ones that resurfaced. Instead, they were forced to experience their worst moments—or even memories that weren’t their own.Those who managed to survive this haunting experience found themselves watched by strange creatures, and in turn, were granted their powers.As if the world weren’t already thrown into chaos, these same bizarre monsters began to manifest on Earth, threatening humanity with the very real prospect of extinction.Amidst this upheaval, a small, seemingly insignificant beast was born. But it quickly rose to power, only to be betrayed and killed in a cruel twist of fate. Or so it seemed—because somehow, the beast found itself reborn in the body of a human.

Zavier met Cosmic Consciousness after his death. He was satisfied with every system that Cosmic Consciousness exhibited, so he wanted all of them. Surprisingly, the Cosmic Consciousness obliged him.

Zavier was reborn in an isekai full of magic and alchemy. Now, he had many routes to upgrade. Interestingly, to coordinate these systems, Cosmic Consciousness gave him the gift of being able to duplicate himself. He could clone a finite number of himself to manipulate these systems.

Magus, Alchemist, Mesmer, Tamer, Hunter, Vampire, Werewolf, Dragonknight, Necromancer.....

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By the way, it wouldn't appear NTR or some bullshit harem of courtships. MC of course will have harem but not for cliches.

Forty years ago, demons invaded the eastern continent. Coming from another realm, they hunted the humans, and people soon began to wage war with them. Before long, there were those among the humans who inherited the demons' abilities.Demon hunters are currently the most in-demand profession. Although the chance of dying during a raid was high, the hunters were mostly popular among the common people. If you have some demon blood in your body, then the path to the Hunter's Association is open to you.Year 2066, Seoul. The territory of the former city is divided into three parts. Green Zone, Orange Zone and Red Dangerous Zone. Although mostly ordinary people and workers lived in the green zone, there was a chance for demons to get into it. That's why demon hunters patrol the whole area, sacrificing themselves for the lives of people.The main character, Lee Ki-hyun, inherited 50% demon blood and became the world's first SSS-ranked demon hunter. He will have to go through the path of a demon and learn the truth about his parents to save humanity.

Lee Seongjin, the strongest hunter who defeated the demon king.
He possessed the body of the pig tr*sh Third Prince, the Holy Imperial Family’s shame.

But the members of this family… there’s something strange about them?

‘Overpowered’ Holy Emperor.
‘Regressor’ First Princess.
‘Player’ First Prince.

Lots of trouble and lots of words
The story of the Holy Emperor and his children.