So I only very recently entered the world of shifters and I don't know what all the "rules" are yet (you know, besides being awesomesauce, which should be the #1 rule BTW). But Nightshade was nothing short of amazing and extremely engaging and entertaining. 
 Calla is the Alpha of the Nightshade werewolf pack. She's known all her life where her future lays and it's not with the human boy, Shay, who captivates her. She's to mate with the Bane Alpha, Ren, and together, they will lead their new pack of wolves, secret from the human world, although they do live among them. 
 There isn't really anything negative for me to say about Nightshade, it's really just that good. One nit-picky detail: [SPOILER ALERT] When Calla changes Shay, his transformation is just too easy and the whole episode is glossed over. I thought more could have gone into that to make it really heart-palpitating. [/SPOILER ALERT] 
 Nightshade has so much going for it that I think readers of paranormal/young-adult will like: it's fast-paced (there is always something going on), it's easy to identify with, it's sexy (grrrr), and it has that special paranormal element, that, while it's not unique, the author twists to make it her own. Andrea Cremer hits a home run with Nightshade and I can't wait to read Wolfsbane!