Of the first three stories (Alpha & Omega, Cry Wolf, and Hunting Ground) this is definitely the most romantic. The pacing of the story is tight and moves along quickly, and we really get a chance to delve into the politics of the werewolves - around the world. At the same time we get to know Charles and Anna even better, and watch their relationship grow, which is my favorite part. 
 Anna still has some issues with the abuse she suffered at the hands of her old pack. I love how Patricia Briggs handles this, it's not a constant fear, but it comes through at random moments and overwhelms her. She struggles against it, and talks herself past it frequently, but that's not always possible. It's shown beautifully at the beginning, Charles is drawing deeper and deeper into himself and his frustrations, and Anna has plans to bring him out of it by ambush. There's still that ingrained moment of hesitation about making him mad, what a much larger, more dominant wolf could do to her. Logically she knows he would never hurt her, and she knows that in her heart too, but it's hard to overcome what years of abuse will drill into a person. Even worried about that, Anna does it anyway - because she loves Charles. 
 Seeing their relationship grow, and deepen, is a true joy. The comfort, and easiness between them continues to grow. That she can tease him, tickle him, and have fun with him shows just how far Anna's come. That Charles plays with her, shares private jokes, and can generally be a "lovebird" is perfect. 
 I also really love how they're both adjusting to each other. They talk about it at one point and Anna asks if Charles is as confused as she is, and he says that he's not, but that he's differently confused because he'd had so long to settle into himself and being alone that the transition is different for him. Charles isn't a big talker, doesn't always trust his words to be what he wants them to be, but I love that he makes a real effort for Anna when she needs it. 
 The mystery part of it is interesting, though I don't think it's hard to figure out who the ultimate "bad-guy" is - I can't recall if I did my first time reading it. 
 I think I'll just add some favorite quotes here, nothing too spoilery, but be warned if you don't like to read anything like that :) 
 She gave him a happy look as he followed her out on the water-soaked wooden walk. "This could be fun," she said, then turned, took a running step, and did a couple of back flips - like a middle-school kid at recess. He stopped where he was, lust and love and fear rising up in a surge of emotion he did not, for all his years, have any idea how to deal with. 
 "What?" she asked, a little breathless from her gymnastics. She brushed her wavy heair out of her face and gave him a serious look. "Is there something wrong?" 
 He could hardly tell her that he was afraid because he didn't know what he'd do if something happened to her. That his sudden, unexpected reaction had brought Brother Wolf to the fore. She threw his balance off; his control - which had become almost effortless over the years - was erratic at best. 
 *** 
 "You are a remarkable man, Charles Cornick." 
 He wrapped his arms around her shoulders and put his chin on the top of her head. "I know," he confided lightly. "And often under-appreciated by those who don't know any better." 
 She poked him with a finger and looked up at him. "And funny - though I expect that is another facet of your character that goes unappreciated even more often than your remarkableness." 
 "Some people don't even notice," he said in a mock-mournful voice. 
 *** 
 "Do you remember when I told you that you were my mate - and you responded by telling me you didn't like sex?" 
 She giggled at his smug tone. "I thought it only fair to warn you." 
 *** 
 She was on the far side, leaving two cold feet of mattress between them. He knew that she'd fall asleep like that...and then gradually move over until she was plastered against him. Then he could go to sleep, too. 
 *** 
 "...I love your touch. Touch me anytime. Any place. Anywhere." It was heartfelt, and honest... <<*snip*>> "Pet me," he told her. "I like it."