The Vampire Assassin.

After centuries of living the life of a free spirited, spoiled rich vampire, terrorizing the Eastern European countryside, Veronica arrives in the United States for new prey. But when her actions start attracting the attention of humans she is brought before her clan elders and ordered to reign in her "bloodlust" or be ostracized by the rest of the clan, a fate worse than death. In order to get back into the good graces of the elders, Veronica must become an assassin and kill vampires who themselves are attracting the humans' attention.