Storm Wolf by Jane Godman

Ever since her father was killed just over a year ago by the Arctic fighting force known as the Brotherhood of the Midnight Sun, Odessa Santin has been the leader of the Siberian werewolves. The Arctics and Siberians have been at war for centuries. So when Odessa has sex with an Arctic stranger, it is the craziest thing she has ever done.

Dan Lowell is a member of the Brotherhood of the Midnight Sun. Lowell is aghast when he realizes his mystery Siberian lover is Odessa Santin, particularly as he needs to confront her because he believes she has been poisoning the Arctic environment. The physical passion they feel for each other is equaled by their sizzling animosity as they argue over the allegations.

Lowell soon discovers that Odessa is being framed, and someone is trying to reignite hostilities between the two packs. For the first time ever, the Arctics and the Siberians agree to put aside their differences and unite against a common enemy. As they work together, Lowell and Odessa begin to realize that their feelings for each other run deeper than they thought.