If it's fangs and lots of blood-drinking, this is not your film. Most of the vampirism is very understated... the vampire stalks a prey and turns back to camera to feed; that sort of thing. Be warned: the cover art is not taken from the film.
Levres de Sang/Lips of Blood...
A man recalls an experience as a boy at a castle when he meets a hauntingly beautiful woman. Somehow he's only reminded of this upon seeing a postcard of the castle. He then seeks to track it down, called on by visions of her. His mother tries to stop him, but he eventually is reunited with his pale ageless love.
Rollin later re-edited this film, inserted lots of hardcore porn, and re-released the X version under the title of "Suck me Vampire".