Also known as The Rachel Morgan Series, this book series follows Rachel Morgan, a witch who quits her job at the I.S. (Inderland Security) to start her own independant runner firm (basically a bounty hunter).
It starts with Dead Witch Walking in the middle of a job tagging a leprechaun for tax evasion, as opposed to her past-usual jobs of tagging black witches. It's during this job that we meet Rachel's newest (and unexpected) business partners.
We meet Rachel's backup, Jenks for the first time. Jenks a pixy, is four inches of attitude with dragonfly-like wings. Jenks is one of the most enjoyable characters to read. He is often underestimated, due to his lackluster size. In all actuality, he's one of the most dangerous, being able to "pix" (sort of an itch powder) whom he chooses with his pixy dust (pixies dust, not bleed), sneak around with high chance of being unnoticed, and a knack for technology that allows him to loop security cameras with little effort.
We also meet Ivy, a living, high-blood (born with the virus forming her from the womb) vampire. Unlike Jenks, Rachel knows Ivy already, having been her punishment for not conforming to office politics. Ivy is one of the more dark characters. Though still enjoyable to read, she has a past that's shrouded in both mystery and shame and is quite sad to learn about at times. Being a living vampire, she has some of the perks of the undead vampires: enhanced hearing and speed; extreme strength, being able to break an arm with little effort; and the ability to pull an "aura," sort of like threatening, only much scarier. Hard to explain. Being a high-blood living vampire gives her sharp canines and a hunger for blood (though she abstains). One of Ivy's many quirks is her tendency to plan everything, down to every last breath. This fact irritates Rachel to no end.
Rachel is a white earth witch. Her power comes from plants and three drops of her blood to quicken it. She can store it in potions or amulets. Her most powerful "offensive" magic is sleepy-time charms (which obviously, put her enemies to sleep). She has strong morals and will not change them, even under her I.S. death threat for quitting. She's a bit naive, but only so much that she forgot that the world isn't going to protect her like the I.S. did. Having quit her job, she realizes that she has to rely on her friends to help her, something which is new to her and very hard for her to do.
As the series progresses, they learn to live with each other, becoming not only great business partners, but also incredibly close friends.
Throughout the series, we meet more characters and learn of more species. Fairies, Weres, demons, elves, and trolls being the brunt of it.
Full of magic, excitement, danger, and humor, the Hollows is one of the best urban fantasy series out there. Only nine books out now (at least three more coming), numerous short stories (in anthologies), a comic prequel from Ivy's POV (and more comics coming, though not particularly from Ivy's POV), and the coming Hollows Insider (a world book; facts, fictional newspaper clippings, species descriptions, etc.), the Hollows will suck you in faster than you can say Rhombus! (Hint to later books, though no spoilers.)
The Hollows is one world that will continue to influence my life in ways I can't even imagine. I encourage you to give the series a try.