Who is Lieutenant Karrin Murphy?
Karrin Murphy was the director of Special Investigations out of downtown Chicago, a de facto appointee of the Police Commissioner to investigate any crimes dubbed unusual. Vampire attacks, troll maraudings, and faery abductions of children didn't fit in very neatly on a police report--but at the same time, people got attacked, infants got stolen, property was damaged or destroyed. And someone had to look into it.
In Chicago, or pretty much anywhere in Chicagoland, that person was Karrin Murphy.
-- Storm Front by Jim Butcher
She is blonde, petite, has a cute button nose, and regularly wins martial arts tournaments. She's a tough broad with marriages behind her, a large extended family who really care about her, and her sense of justice is the driving force behind her actions. She is a great character.