Top 21 in Top 25 best anime about vampires you will want to watch right away.
Opening theme 1 of the vampire anime Blood+
Blood+ is the best anime about vampires quite specially, it has changed the definition of vampires, although functionally the main antagonists still seem to be the same. Although the action scenes and character development take up most of the fun, it is the slow construction that makes the audience watch and speculate until Blood+ ends.
Even more impressive when it is revealed piecemeal, from the perspective of the main characters, thus making Blood+ such a classic 'vampire' anime.