Empress Serena died in battle to protect her daughter and entrusted the infant to the laundress, Martha. Masha, out of jealousy, switched the swaddling cloths, making her biological daughter Rosa the princess, while the true princess Ivy was reduced to a wingless female servant. Eighteen years later, Ivy participated in the Saint's Wing Trial for freedom and accidentally awakened the Empress's relic, revealing her bloodline. The False Princess Rosa and Augustus repeatedly misunderstood and persecuted her, even tearing off her wings. Ivy, under the protection of the Vow-Keeper Knight Kain, awakens her Eight-Winged Power, uncovering the truth behind the switch and the Fallen Wing conspiracy. In the end, Rosa's attempt to assassinate her father and seize power failed. Ivy ascended the throne, abolished slavery, and became a true empress.