Sin System: Demonic Harem After Reincarnation

Lucian Matis was a traveler of a world where magical creatures are made. He Kevin and Adam who helped him settle in this world. Lucian liked this world because it was full of things he didn't know. He was killed by a blue demon dragon because it was his first assignment, This made him Lucian come back to life. Later, Lucian found out that he had been reborn on earth to help him get ready for the The Dark Universe mission. Something bad was waiting behind the curtain. It was found that there was a crack that let to the Dark Universe. This is a world where strange beings who could destroy the earth lived. On the other hand, Lucian's past experience will be used to build a copy of the Dark Universe that will be used to teach new recruits. This system is called the Earth Protection System. Chips were put into the brains of hosts while the Earth's Protection System was being built. Members of the earth's defender mission must now be ready for the future and have a plan to help them grow and get ahead.

Little Sky, an earthling human, is the lowest ranking Knight on earth, regarded by many as the weakest Knight in existence. Little Sky has always hated that he was weak, he trained harder than anyone did, but that didnt change his status of being weak. Little Sky has always been disdained and look down upon by other Knights, they would always laugh and teas on how weak he was. He had thought of quitting so many times But, burdened by his mother's hospital costs and a big loan which is said to be left to him by his father, he had no alternative but to risk his life every day inside the demon grottos, despite his limited strength, which could barely kill the weakest demon. But all that changed when he activated the crazy Devouring system, which granted him the most powerful constitution in the universe; endless evolution, as well as the ability to devour everything. Sky would go from being the weakest to the absolute strongest, saving humanity and the entire universe from the catastrophic demon invasion. with his system nothing in this universe could stand in his way.

Everything was taken from him, the girlfriend he loved, his promotion and even the means to work elsewhere. However, everything changed when the Ethereal Adventure System arrived. a system that would give him real life money and superhuman abilities for completing task which mainly involved travelling to other worlds. Would he grasp this opportunity completely? would he become the apex of humanity. you can check this out by following his journey. I own the copyright to this cover including all parts and cover

Elrick Aldof—A lousy young man whose life is full of misery and failure at all costs, unexpectedly discovers a system that magically has an infinite arsenal, full of various weapons! In the face of the irregularities in his life, he was shocked when the terrible 'Mad Wolf' virus hit Okazaki City overnight. Suddenly, the town where he lived became deserted because there were rampant zombies, and the streets were full of corpses in the form of zombies. How will Elrick Aldof act in facing the system to save his life and the lives of his relatives and close friends?

Travis's world is shattered when his girlfriend Abigail dumps him for a wealthy playboy, Calvin, and humiliates him in public. But just as Travis is about to lose hope, a mysterious entity, the Grand System, appears, offering him a chance to turn his life around and become rich and famous. Will Travis accept the offer and embrace the unknown, or will he let his past define him?

Meet Maximus Prime, the once abandoned, betrayed, and humiliated by his girlfriend and family. On the verge of giving up and accepting a crime he knows nothing about, Maximus was gifted with a Tycoon system. Maximus became superrich with the system and his Cybersecurity skills got to the highest level. Whenever Maximus upheld justice, he was rewarded bountifully by the system. A sneer rested on Maximus' lips: "It's time to play some dirty game." Maximus smirked, looking serious. His family, down to his ex-girlfriend and best friend, Maximus was ready to face them again. Including the hidden enemies that want him dead. Maximus was coming for them!

Othniel was a poor man who had a major accident due to his wife's betrayal. For three days, Othniel was in a coma and kept having strange dreams. He got a choice from the dream. First he will get 10,000,000$ or work with the system. Then Othniel decided to choose to work with the system. And that's when Othniel realized and immediately got a job from the system. Challenge after challenge, Othniel must be able to complete. Every time Othniel succeeds, he will get an extraordinary salary.

In a galaxy where civilizations have been systematically destroyed by an unknown force, the leaders of the surviving civilizations come together to form a last-ditch effort to save themselves and their people. They construct a massive starship, the "Last System," and its crew must navigate through treacherous space and overcome unimaginable challenges to find the source of the destruction and put an end to it once and for all. Along the way, they must decide whether to offer aid and support to struggling civilizations or focus solely on their mission and the survival of their people. As they get closer to the source of the destruction, they uncover a dark secret about the true nature of the threat they face and realize that their mission is not just about saving themselves, but about protecting the entire galaxy from an ancient evil that threatens to consume everything in its path. The crew of the Last System must make the ultimate sacrifice to stop the threat and ensure the survival of all life in the galaxy

Jin returned from another world. The dead rise and eat the living. Without a way out, he accepts his fate and lets the undead eat him. “Was that… Me? Or rather, my body? W-What happened to me…!” [Do you want to activate the Undead System?!] A/N Many thanks to Sera Execfia for the gorgeous Cover art.

William, an internationally recognized game developer and also the mafia lord of the underworld, was on every country's wanted list because of his unparallel hacking and large control over highly classified information and power. Betrayed by his biological brother, who shot him to death, he was reincarnated in the world of warlocks. In a world where magic reigned absolute, he was constantly abused for not having magical power and was eventually sold to some slave merchants by his new family, where life became even hellish. Beaten to coma after being caught trying to escape, he woke up with a system which provided him with a second chance to prove himself. Being granted the ability to copy other people's magic by writing their names in the ancient grimoire. Jerouch was set on walking a path where even gods have fallen. What end would be the path of a nobody who ascended with the system as his support in a world full of mythical creatures, gods, dragons, and demons…