The Celtic lore of the British islands includes a number of vampiric spirit-women, including this one, pronounced "baavan shee."
The same as banshee, "Baobhan Sith" means "spirit woman" or fairy woman," but is generally employed to mean a kind of succubus, very dangerous and evil. She can only be killed by cold iron.
She appears as a beautiful young woman who dances with men until they are too exhausted to defend themselves. Then she drinks their blood!
She is also a shape-shifter and sometimes appears as a hooded crow. Even when appearing as a beautiful woman, she has deer hooves which she keeps hidden under her green dress. Often several baobhan siths appear together as a group.
The baobhan sith is described in some books as belonging to the broader class of Scottish spirit-women called the green glastigs, though these are usually solitary spirits and generally do not drink blood.
One Scottish tale about the baobhan sith begins with four men on a hunting trip playing music and dancing and dancing by their campfire one night. Three danced and one played. One of them expressed the wish that they had some young ladies to dance with. Suddenly four beautiful women wearing green dresses came in out of the dark. Three of these women began immediately to dance with the three dancing men. The fourth stood next to the one who was playing the music. The music player became alarmed when he saw blood dripping from his comrades onto the ground. He fled to where they had their horses tied and hid under them. The lady who had been standing next to him pursued him but she was repelled by the iron in the horseshoes. She circled around until dawn. After the sun rose, he found the dead bodies of his friends. There was not a drop of blood left in them.
spooooky story lifted from:
http://www.zyworld.com/vampirelore/Gallery1.htm