This is the first of The Mortal Instruments series. There are four books published but I found a listing where another two books are planned for publication. She has also written a trilogy of prequels to the series in the Infernal Devices series.
This was pretty entertaining reading. It is young adult fiction set in our modern world but within our world live a variety of demonic creatures as well as the human angel hybrids who hunt them called ShadowHunters.
An average 15 year old girl named Clary stumbles onto the fact of this "other world." For unknown reasons she can see past the glamour that is created for the mundanes (plain humans). Soon, she is embroiled in a mystery and the search for her missing mother.
I thought this was a good way to blend the supernatural world and the real world together. It's also a pretty good story line as to why kids are saving the world and solving the problems rather than the adults.
I have the first three book of the set and if all three stay this fun and easy to read, I will probably read the whole series. I think after the first three of this series, I'll probably ready the prequel books and then get back to Mortal Instruments.