Mortal Instruments: City of Bones

I have read a bit more of the book now, and I have met 2 new characters called Isabelle and Alec. They seem very interesting and I feel like they both have many deep and dark secrets...
I'm at the part where Clary has just been attacked by a demon and she has just woken up at the infirmary in the Institution, with a huge headache and a very grumpy and annoying Isabelle.
The storyline is really developing and I am loving all the new characters that have been introduced.
 I can't seem to be able to put this book down, its so good!