I adore this author - the Raine Benares series is one of my all-time favorites. It's not too heavy, has a ton of humor with damn good sexual tension woven throughout it.
The Grendel Affair suffers from First book syndrome/itis - whatever. Information overload - not a ton of character development. It's Really busy. Lots of characters, reads more like a procedural than any sort of fantasy. It's creative -and has its fair share of funny moments/dialogue - but it wasn't nearly enough to overcome the problems.