After reviewing the IMDB cast list for the movie The Ninth Gate, I noticed there was an uncredited "demon" character played by Jane Bradbury. I just recently watched the movie, and have seen it several times before, yet I do not recall seeing this woman or any "demon" character other than possibly "The Girl" who protected Corso, and "The Girl" was played by Emmanuelle Seigner, so I know it wasn't her. So, the question is where was this "demon" character in the movie?
You can only see this demon in the director's cut version of the movie. You can also see it in deleted scenes.
When you are looking at the unique scenes in the director's cut it is scene #4.