Kingdom of the Sun follows Mirage, a young royal from a kingdom where magic is forbidden-and until she is sold off to pay her father's debts, that was fine by her. Only saddened to leave her brother and loyal handmaiden, Diana, she accepts her fate of being nothing more than a bargaining chip. That is until it is apparent that the emissary who purchased her is a magic-wielding Tessiah. When she is brought to a mythical kingdom where the alleged monsters she had grown to hate reside, she must learn to reimagine a world where magic is at her fingertips. Thrust into brutal training and complicated relationships, she must reforge her mortal heart in fire or burn in her madness.

Mirage discovers the beauty of magic and love as she develops intimate relationships with the very people she was taught to fear. The Tessiah were loyal, loving, and brave, but she would never have known that if not for the woman she hated most in this world, who dragged her to the magical kingdom she would now call home. Yet in her brightest moments, the shadows of her brother hang at the back of her mind, as he is still in the clutches of her despicable father.

Drawn into dangerous plans alongside Jesper, a Tessiah who is notorious for his questionable morals and affinity for dangerous magic, who seeks to avenge his deceased parents-Mirage reluctantly agrees. Desperate again to see her twin brother and share with him the secrets that she unearthed, she embarks on a mission that will destroy her.

When she's captured by the very sibling she set out to save, her newfound allies must decide how far they'll go to bring her and Jesper home. Meanwhile, Diana, imprisoned and desperate, reaches for a forbidden power that dooms them all. As the tide shifts, and danger pours in like a tidal wave, Mirage must decide, is love worth losing everything for?