After a devastating plague decimates Fortna, Nina, a girl with striking blue eyes, loses her parents and turns to thievery with fellow orphans to survive. Unexpectedly abducted by a group of enigmatic men, she discovers her captor is Azure Seth Fortna, the kingdom's prince. Azure's deceased half-sister, the reclusive princess-priestess Alisha, was meant to marry a prince from Galgada before her tragic demise. Despite Nina's lack of resemblance to Alisha, they share the same unique eye color. Azure, aiming to avert war between realms, enlists Nina to impersonate his sister. Nina, with little left to lose, agrees to the deception. Guided by Azure, she navigates the challenges of posing as royalty. The destinies of two kingdoms now pivot on Nina's actions, as she resolves to align the universe in her favor.