The Nine Lives of Chloe King by Liz Brazwell contains the three Chloe King books previously written under the pen name Celia Thomson. This is a MASSIVE book. The three books together make for a book so large that it takes two hands to hold (and isn't going to work in the bathtub). If you've got an e-reader I'd suggest buying the digital copy even if it is more expensive.
The Nine Lives of Chloe King starts out with Chloe falling off of the Coit Tower on her sixteenth birthday. Aside from a little blood she is just fine. Chloe then starts to develop. She becomes confident with her sexuality and she develops strange catlike powers and finds herself being chased by an unknown assailant.
I had a hard time getting through the first of the three books in the series. Chloe is self absorbed and fairly unlikeable. She bounces from boy to boy and treats her friends badly. The plot also moves very slowly. Chloe doesn't find out who she is and the reader isn't given any answers at all until the last few pages and that still isn't much. The mytholgy is different from much of what's out there
Appropriateness: In the first few chapters Chloe drinks and gets hot and heavy with a stranger she met in a bar (although there is no sex). She does have a nice relationship with her mother (although she isn't totally truthful) There is also a minor subplot about Chloe getting her period that would turn off male readers. I would peg the interest level at 13 +