My Revenge began with One Dragon egg

Twenty years ago, the Dragon King's wife gave birth to a black egg—deemed an omen of disaster and cast into the sea. Her mother tore off her own Heart-Scales to protect the egg, and was reduced to slavery. Twenty years later, Sera—a girl raised on Dragon Cliff—descends the mountain to find her family. She rescues her mother, and stands against the false princess and her tyrannical father.