Princess Aurelia is brutally framed and poisoned by her jealous adopted brother Cassian. Her personal guards are massacred, and she is sentenced to death by burning at the stake. After her death, she strikes a black-gold marriage pact with Dante, the demon who rules the realm of souls. In exchange for regaining a physical body and returning to the mortal world to seek vengeance, she agrees to become his bride once her revenge is complete.
Aurelia hides her true identity as she infiltrates the military barracks, seizes a legendary divine weapon, and exposes a scandal involving moldy grain rations. With Dante secretly watching over her, she systematically unravels Cassian's schemes step by step. In the end, she presents irrefutable evidence of his regicide during the coronation ceremony, kills the enemy with her own hands, and ascends to the throne as queen. She then honors her pact, ruling both the mortal realm and the underworld alongside the demon.
