An erotic novel of The Phantom of the Opera.
Phantom of the Opera: Now with more porn! From amazon's description:
Her erotic awakening...
Condemned to the catacombs below, Erik has desired his obsession from the shadows, careful to keep his identity, and his secret, in the dark. Only he understands Christine's extraordinary talents and her beauty. Only he can pleasure her like no man has before. But his sensual power comes with a price-and a risk to everyone who stands between them. For Christine too is succumbing to her most forbidden and dangerous desires-and to the Phantom who's making them all come true.
Wow. Just. Wow. I can't believe someone got this published.
...well, after seeing all the Jane Austen fanfic, maybe I can.