Demonglass was a fantastic second book in a series. The change of scenery allowed the mythology to develop and kept the series from being a monster of the moment book. I really enjoyed the relationship between Sophie and her father and it was nice to see a parental figure taking a large role in a book for this audience. The twists were surprising and the mystery (and the romance) made for a great read.
Appropriateness: This novel is fairly tame. There's one scene where the kids go to a club but Sophie does not drink. The romance is set at a distance and only includes kissing. I'd set the interest level at 13+ Hex Hall