On the dusty streets of the castle town Dayah in the Fortna Kingdom, a young orphan named Nina steals for survival. Experiencing one tragedy after another, she has little to hope for in her life. Believing it best for Nina, her closest friend, Saji, hands her over to Second Prince Azure Seth Fortna, who has been searching for someone with unique and intense deep-blue eyes—just like Nina's.

The kingdom's princess, the revered Astral Priestess Alisha, has recently died on her way to the Galgada Kingdom, where she was to marry the tyrant First Prince Sett. However, her death is concealed for political reasons, and that is where Nina needs to step in. With nowhere else to go and no one to turn to, Nina assumes Alisha's identity and future duties. But with each moment spent with Azure, Nina feels herself drawn to his warmth, fearing that once she is wed to another, nobody will remain to remember her true self.