Nightmare Level Up: Dream Trial of Devil's Heir

Every night, he fights to survive. Every morning, he wakes up being stronger. But Kairo didn’t ask any of this. The Devil chose him. Not as a servant, not as a pawn, but as a candidate. Dragged into a brutal game to prove his worth, Kairo is watched at every step, at every level by the Devil who marked him and who doesn’t want him to win. Each trial makes him stronger. But every failure takes something from him. And the deeper he goes, the less human he becomes.