Emilia, a broken-winged butterfly girl treated as a "waste," is sent to the palace as a sacrifice. Instead of dying, she meets the cursed first prince, William, a black-winged butterfly king losing control. Her touch pushes his decay back, she is the legendary fated wingmate who can light his golden lines. Bound together, they suppress the curse and gray erosion. But the gray comes from Rena, a hidden Moonlight Butterfly survivor who planned the clan's massacre to steal Emilia's silver light. When the truth is exposed, Emilia merges silver, gold, and gray, grows three-colored divine wings. William finally faces his past sins and ends Rena's madness with his brother Damian.
