My Husband,The Dragon King

Everyone mocks Alice, a disgraced wife raising her "bastard kids" in a stable—until the twins' fifth birthday, when the boy sprouts golden dragon horns and the girl grows black wings. When their cruel stepmother throws them into the river, their dragon bloodline awakens, the son searches for their Dragon King father, and the King of the Underworld appears—revealing that the "lowborn" mother and her children are actually the Dragon King's wife and heirs.