Vampire King by Joanna Mazurkiewicz

Tired of waiting around for true love, Cindy–a young girl from the Farrington Kingdom whose father died years ago, decides to take matters into her own hands.
King Caspian II organises a ball for his son and invites every eligible woman in the Kingdom, meaning Cindy’s invited too.
The trouble is, her stepmother, Ida, rips Cindy’s dress to shreds and forbids her to attend the ball. Cindy trips over a drunken a woman of the night who’s blessed with extraordinary magic. She transforms Cindy’s tattered dress into a beautiful ball gown, a carriage from two beggars and sends her on her way.

But the Prince doesn’t catch her attention, instead it’s King Caspian himself who lures her into his bed. After a night of pure passion with the King, Cindy discovers that he isn’t human at all, but a vampire, hell-bent on having her in his bed again.