If you've read Terry Pratchett's 'Witches Abroad' you'll already have the basic concept: Fairy Tales want to be real, and do their best to manifest in the world, their consequences are often harmful, both to the main players and to unfortunate bystanders. In Pratchett's novel, Granny Weatherwax and her two companions thwart any tales they come across in their travels. In McGuire's book, there is a special agency charged with dealing with them. Armed with their printed copies of the Aarne-Thompson Index (en.wikipedia.org/wiki/Aarne–Thompson–Uther_Index), they watch for manifestations and deal with them as they arise.

I'e found the two books in this series funny and good to read. They do not have the mythic resonance of the October Daye series, but neither do they suffer from the long internal monologues and repetitions of that series. Good reading