Wikipedia
The Alkonost is, according to Russian mythos and folklore, a creature with the body of a bird but the head of a beautiful woman. It makes sounds that are amazingly beautiful, and those who hear these sounds forget everything they know and want nothing more ever again. She lives in the underworld with her counterpart the sirin. The alkonost lays her eggs on a beach and then rolls them into the sea. When the alkonost's eggs hatch, a thunderstorm sets in and the sea becomes so rough that it becomes impossible to traverse. The name of the alkonost came from a Greek demigoddess whose name was Alcyone. In Greek mythology, Alcyone was transformed by the gods into a kingfisher.
Alkonost is a Russian epic folk metal band formed in Naberezhnye Chelny, Tatarstan, Russia in 1995. Starting small and gradually building a local Russian fanbase, they are now known to rock fans throughout Eastern and Northern Europe.