They wanted a hero. Instead, they summoned the man who would become their final nightmare.

He was once the weakest member of the hero party-a low-ranked incubus surrounded by Titans, Archangels, Dragon Slayers, and chosen warriors blessed by fate.

They mocked his bloodline. Used his mind. Stole his victories. And when he had nothing left to give, they threw him away.

Then he died.

Now he has returned thirty days before the summoning, armed with a ruthless leveling system that reveals loyalty, desire, hidden bloodlines, and forbidden potential. This time, he will not stand behind the heroes. He will build something far more dangerous than a party.

One bond at a time.

One awakened bloodline at a time.

One powerful woman at a time.

Phoenix. Vampire. Siren. Dragon Heart. Every bond makes him stronger. Every awakened bloodline becomes another weapon in his rise. And every woman who chooses him brings his legion one step closer to becoming unstoppable.

The heroes think they are preparing to save another world.

They have no idea the "trash incubus" they once betrayed is already rewriting the future.

A dark adult harem LitRPG fantasy packed with villain progression, isekai revenge, system leveling, bloodline awakening, and the rise of an SSS-rank demon legion.