The Undead Pool by Kim Harrison

Supernatural superhero Rachel Morgan must counter a strange magic that could spell civil war for the Hollows in this sexy and bewitching urban fantasy adventure in acclaimed New York Times bestselling author Kim Harrison's Hollows series.
Witch and daywalking-demon Rachel Morgan has managed to save the demonic ever-after from shrinking, but at a high cost. Now, strange magic is attacking Cincinnati and the Hollows, causing spells to backfire or go horribly wrong, and the truce between the races, between Inderlander and human, is shattering. Rachel must stop this dark necromancy before the undead vampire masters who keep the rest of the undead under control are lost and all-out supernatural war breaks out.
Rachel knows the only weapon to ensure peace: ancient elven wild magic, which carries its own perils. And no one knows better than Rachel that no good deed goes unpunished . . . From Goodreads.

I really like this series by Kim Harrison a lot. In this book Rachel of course has to save the world again, mostly the undead vampires. Take on an entity and also figure out her feelings for Trent. I am a bit sad that it sounds like the next book is going to be the last at the same time I think it is the right time.

This book qualifies for:
2014 Ebook challenge
2014 Full House Reading Challenge
You Read How Many Books? Reading Challenge 2014
Crazy Challenge Connection Chinese New Year Challenge
Crazy Challenge Connection: 1000 Member Celebration!
Goodreads Reading Challenge 2014
Crazy Challenge Connection - Sub-Genre Challenge 2014
Nothing but Reading Challenges - Spell it Out - Animal Alphabet (U-quail)
Crazy Challenge Connection Bard of Avon