"Vampires are mythological or folkloric revenants who subsist by feeding on the blood of the living. In folkloric tales, the undead vampires often visited loved ones and caused mischief or deaths in the neighbourhoods they inhabited when they were alive. T
hey wore shrouds and were often described as bloated and of ruddy or dark countenance, markedly different from today's gaunt, pale vampire which dates from the early Nineteenth Century. Although vampiric entities have been recorded in most cultures, the term vampire was not popularised until the early 18th century, after an influx of vampire superstition into Western Europe from areas where vampire legends were frequent, such as the Balkans and Eastern Europe,[1] although local variants were also known by different names, such as
vrykolakas in Greece and
strigoi in Romania." - Wikipedia
http://en.wikipedia.org/wiki/VampireThe traditional appearance of vampire doesn't have to be used. Could be an ugly, disfigured and malovelent thing. Also the idea of not giving it an obvious consciousness is good. Though the consciousness can be done well if it shows the sociopathic or deranged nature of the mind. Possibly a consciousness that is fragmented and very erratic and chaotic, but still produces coherent events and exhudes a large amount of manipulation, being even harder to track because the creature seems to leave a very non-sensical trail, discerned from its actions which always seem to be chaotic but do lead to a certain goal of the vampire.
Another way, would perhaps be to not give it a name, refer to it as 'the creature' or something. Even as a serial killer, and have it revealed only at the end what it was. Or just let people sum it up from the clues and never know if it definitely was a vampire. Not referrign to it as a vampire stops people expecting 'typical vampire' thoughts, actions and possible counteractions.
Keep it a mystery