Ariadne's Diadem

When Ariadne's Diadem disappears, Bacchus blames Gervase, Duke of Wroxford, and a hapless faun called Sylvanus. The two must find the diadem, but Gervase turns into a marble statue by day. To break this spell he must win Anne Willowby, but only after dark. She rebuffs him, and there's little help from lusty Sylvanus, who yearns for nymphs. . .  Regency Paranormal Romance by Sandra Heath; originally published as The Faun's Folly by Signet