Wolf Caller — Silvia Violet

As their world draws closer to war, the future of Albion is in the hands of a werewolf pack who must protect the country's most carefully guarded secret, a new magically-generated power source. Rumors about the mysterious Lord Derek Valmont abound, but no one in Albion's Upper Circles knows the whole truth. Valmont is an alpha werewolf and an operative for the Office of Clandestine Affairs.

Captivated -- literally -- by the hauntingly beautiful Serena, Valmont is furious that he can't break the hold she has over him in wolf form. When she flees their first encounter, he drinks in her lingering scent, determined to find her again. When he's human, she'll be the one powerless to resist.

Serena may not be able to control the man as she does the wolf, but she's got an agenda of her own, and she's set her sights on both Valmont and his second in command.

This book was originally released as a series of novellas, Control, Power, and Yearning. It has since been updated and re-edited.