THE DEMON LOVER
Scottish Folklore
A type of Spirit/Fairy
This spirit is the subject of many ballads in Scottish folklore. In the legend this “Elfin knight” wins the love of a mortal maiden and they become betrothed. He swears that although he has to leave her for a while, he will return and they will be wed if she will be faithful to him. Seven years passed, and in that time, the grieving maiden found another, married him and bore a child. The fairy knight returned in a galleon with silken sails and golden masts, and immediately sought his betrothed, who was once more under his spell. This time he carried her off on his galleon, which, only three leagues from shore, sank forever to the bottom of the sea.
Source: Spirits, Fairies, Leprechauns, and Goblins Encyclopedia