Well, what we have here is a film featuring a beautiful Japanese girl-vampire, of the good kind mind you, dressed in school uniform, toting a sharp Katana sword, able to perform breathtaking acrobatics, has a mysterious past and is hell-bent on a mission of vengeance. Dude, what more do you want? An Academy Award? Well, then this film is not for you.
Actually there was one thing that irked me, and that was the representation of the demons, flying as dragons. That did not come off well. But then I have never seen the Manga version of this film and cannot say if it's a good adaptation in that respect.