Human princess Selina is cruelly cast aside by her own royal family — publicly stripped of her title by her father and offered as a sacrifice to the demon race, all to buy the human kingdom a fragile peace. At her darkest hour, her dormant ancient Demon Emperor bloodline awakens, and the demon general Kaelos kneels before her in public, honoring her as the future Demon Emperor. One by one, the demon prince, the werewolf prince, and the vampire nobles are won over by her — their exploitation and contempt turning into death-defying loyalty as they become her mightiest allies. Step by step, Selina sweeps away enemies within the demon realm, crushes rebellions, and commands all races, rising to become a candidate for the demon throne. When the human kingdom betrays its word and launches war, she returns in force at the head of a demon army to settle old scores with the royal family that once betrayed and trampled her. Faced with her father's repentance and her sister's pleas for mercy, she flatly refuses to return to the hypocritical human court. In the end, Selina ascends the supreme throne, unites the human and demon realms, and establishes a new imperial order of equality for all — regardless of race.
