Seirei Tsukai no Blade Dance - Volume 16, Chapter 6 - The Imposter Demon King

To reward Meng Fan for his bravery before his heroic death, the cosmos rewarded him with a ‘system’, sending him back in time to three months ago, alive.

- Description from Novelupdates

Original name: Prince Charming's Next Door, finished. One day, she slept with him accidentally. Two month later, she found herself pregnant, so they got married with baby. “Mr. Gu, I like the dishes of this restaurant.” Then the chef of that restaurant was hired as theirs. “Mr. Gu, I like the bags of that brand.” Then the designer of that brand was employed exclusively for her. She thought of herself as a stranger to him after marriage as she had always been, but in fact he doted on her totally beyond her imagination. He would satisfy all her demands, except letting her find a job. She kind of got anxiously bored at home, so she sneaked out to find herself a job. However, whichever company she was hired by would go bankrupt somehow or other. Finally, she got to know it had been always him who had done mischief surreptitiously. She went to question him angrily, but he gave her a job with a smirky smile. The next day when she went to take the office with delight, she found her employee ID card on the desk said ‘Name: Qin Zhi’ai, Position: Wife of Gu Yusheng’.

“Everyone deserves a happy ending, don’t they?”…In the brutal fantasy RPG Fall of Ares, saving the world came at a cruel price — the deaths of every heroine the player had grown to love. No matter how skilled you were, their sacrifices were inevitable. The game warned you not to get attached.But one young man did.After beating the game and lamenting their tragic fates, he wakes up in its world — reborn as an extra, armed with one mission from a mysterious system:[Change their endings. Let them live.]Now enrolled at Mysteria Academy alongside the heroines doomed to die, he must rewrite fate itself. For every girl he saves, he’s rewarded. But the world resists change. Calamities draw closer. The true enemy — the Children of the Sky — are watching.And one of the heroines… remembers it all.

In a contaminated world on the brink of collapsing under countless dungeons, a harsh place where if you were unable to summon a creature, it meant you could die at any moment. Alas, the chance of summoning was very low for anyone—except nobles.On a fateful day, an unemployed guy from earth was reincarnated as a nameless slave and had contracted an illness—mana circulation disorder—that would prevent him from living past 30.His only chance was to summon something decent. Luckily for him, a second chance appeared… A challenge from the gods… By getting through it, he finally gained what he wanted.A sword demon....one of demon kings.[Do you want to evolve your summon?][Your summon has two paths to evolve]–[Hellfire Demon]–[Wind Demon][Do you want to use 2,000 Chaos Points to unlock another evolution path?]–[Supreme Sword Demon][Description]: A slave demon… An ancient demon… An extinct demon… They possess swordsmanship unparalleled in all of hell; no demon can defeat them. However, what all demons in hell fear is their ability—even demon gods are afraid of them. Each time they kill someone with their sword, the victim's existence is obliterated from the world. No one can remember them after they're dead.However, that was just the beginning of a Godslayer’s fate when he figured out the reincarnators. And unluckily, the world should have existed only one reincarnator. He had to kill them to survive, or they would kill him.[Author’s Note]*Is the MC a slave? Yes, he is, but it’s just a leftover label from his old identity in this world. The moment Alaric, a fourth-year university student, reincarnated into that slave body, I don’t think he should even be considered a slave anymore. Moreover, he gets rid of his inferior identity once he clears the final challenge of the Nameless God in Chapter 18.*Is the MC OP? Not exactly, since his early power isn’t really a cheat. The real cheat everyone expects only shows up after Chapter 19.