In his previous life, a warrior of the human race fought against demons with blood and ultimately suffered a crushing defeat. Just as the world was about to be devoured by demons, he was reborn with his memories and awakened the unique hidden profession of the Dark Lord. In the eyes of others, he was only the weakest F-level, but in fact, he mastered contract secret techniques and could discover the hidden talents of others and sign contracts to share power. He wandered through dangerous situations, subdued many talented contractors, fought against the evil Shadow Demon organization, and collected fragments of the Dark Lord. As the deadline for the demon invasion approached, he gathered his partners, faced the powerful enemies of various monsters, uncovered the conspiracy, and vowed to rewrite the doomed fate of the apocalypse.
