From Publishers Weekly

After a slow start, debut author Aaron pulls the action together and turns in a romp of a lighthearted fantasy starring an absolutely darling rogue. Eli Monpress is a talented thief with a knack for persuasion and more than his fair share of looks and charisma, and his skill with magic makes him truly formidable. While trying to earn the title of the man with the biggest bounty on his head, Eli kidnaps the king of Mellinor, planning to let him go once the bounty goes up. Then the king's exiled brother pulls a fast one and takes over the kingdom, and Eli must make things right. Aaron's breezy style at times tends toward the farcical and absurd, which may not be what she intended but will keep humor-loving readers looking out for subsequent volumes in the planned trilogy.
Copyright © Reed Business Information, a division of Reed Elsevier Inc. All rights reserved.

From Booklist

Starred Review Aaron’s outstanding fantasy debut is the first in a trilogy about unrepentant thief Eli Monpress, whose goal in life is to amass $1 million in gold. Hoping to accomplish his mission in a hurry, Eli decides to raise the stakes and kidnap a king. He doesn’t realize, however, that snatching the king of Mellinor (an entirely unmagical and rather boring kingdom) will set off a chain of events that will put him in peril from multiple sources, including the powerful Miranda, who is determined to catch Eli. But that’s no easy trick, as Eli is also a powerful magic-user himself; his swordsman-partner Josef carries the legendary Heart of War sword; and their female associate is a demonseed whose powers are terrifying. Fast and fun, Spirit Thief introduces a fascinating new world and a complex magical system based on cooperation with the spirits who reside in all living objects. Aaron’s characters are fully fleshed and possess complex personalities, motivations, and backstories that are only gradually revealed. Fans of Scott Lynch’s Lies of Locke Lamora (2006) will be thrilled with Eli Monpress. Highly recommended for all fantasy readers. --Jessica Moyer