In the Solis Empire, locked in eternal winter, only a marriage between a princess of pure royal blood and the Abyss Dragon can bring back the warmth of the sun. Princess Diana grew up happy alongside her three brothers — until Lorelei arrived. Using a stolen Dragon's scale, Lorelei seized all of Diana's love and standing. Deceived, the three brothers cast Diana aside — even offering her as a sacrifice to slay the dragon. Only after the dragon took Diana away did the truth emerge. By then, it was too late.