How do you know when a book is really good? When you do your best to finish reading it in a single sitting. Yes, Nightshade is just that fabulous. Calla is an amazing character and the writing style flows ever so nicely--also, I'm definitely Team Ren. :P 
 Anyways! I really enjoyed the werewolves--er, Guardians--and the ending was wonderful--although now I'm definitely wondering what will happen next! Am I a terrible person for loving how torn Calla was between Ren and Shay? I hope not--although I still love the dynamic of their romantic struggle. 
 This is definitely a book that I'd recommend to friends looking for YA paranormal romance.