In Muslim folklore there is a female vampiric demon known as a ghul that eats only the flesh of the dead. It breaks into the graves of those properly buried and feeds off their corpses. If it cannot find an easy meal in a graveyard, it shapeshifts into a beautiful woman in order to trick male travelers into thinking that it is a prostitute. Then, once alone with a man, she kills him.

Source: Delcourt, Oedipe, 108-109; Gibb, Shorter Encyclopaedia of Islam, 114, 159; Stetkevych, Mute Immortals Speak, 95-99; Villeneuve, Le Musée des Vampires, 368

The word ghoulas may be the feminine form of the word GHOLE. In Algerian lore, however, the ghoulas is a vampiric creature that appears to men as a beautiful woman, luring them into her castle in the mountains where she will either consume them or turn them into her sex slaves.

There is a popular tale told involving a ghoulas. There once was a prince who was taken on a hunting trip by his jealous brothers. They had hoped to lure him near enough to a castle that they believed was occupied by a ghoulas who would at the very least devour him. Just when the brothers decided they had gotten as close to the castle as they dared and were about to abandon the young prince, they suddenly found themselves surrounded by beautiful women on every side. With no way to escape, they thought they would bide their time and make camp for the night. While the brothers slept, the prince went and tended to his horse. While he was gone, the ghoulas descended upon the sleeping brothers en masse and carried them farther up the mountain to an even larger and more inaccessible castle. The young prince returned to his people and told them what happened. It is said that the band of brothers are still being held by the ghoulas, forced to be the mates of the ghoulas forever.

Source: Knappert, Aquarian Guide, 97; Melton, The Vampire Book, 258