Sianim Series by Patricia Briggs

After an upbringing of proper behavior and oppressive expectations, Aralorn fled her noble birthright for a life of adventure as a mercenary spy. Her latest mission involves spying on the increasingly powerful sorcerer Geoffrey ae'Magi. But in a war against an enemy armed with the powers of illusion, how do you know who the true enemy is-or where he will strike next?

From the #1 New York Times bestselling author of the Mercy Thompson series and the Alpha and Omega novels... Slave. Swordwielder. Spy. Some girls have all the luck... When Rialla was young, slave traders from Darran amburshed her clan, killing all the men and enslaving the women and children. For years, Rialla lived in bondage, until she escaped and fled to the mercenary nation of Sianim. Now she can strike back at her former masters... moreFrom the #1 New York Times bestselling author of the Mercy Thompson series and the Alpha and Omega novels... Slave. Swordwielder. Spy. Some girls have all the luck... When Rialla was young, slave traders from Darran amburshed her clan, killing all the men and enslaving the women and children. For years, Rialla lived in bondage, until she escaped and fled to the mercenary nation of Sianim. Now she can strike back at her former masters. A lord in Darran seeks to outlaw slavery--but there are plots to kill him before he can. Rialla is chosen by the Spymaster of Sianim to prevent the murder--and is plunged into a world of deadly magic... "Plenty of action."-- Locus less

From the #1 New York Times bestselling author of the Mercy Thompson series (Frost Burned, Night Broken) and the Alpha and Omega novels (Fair Game, Dead Heat) Sham had spent most of her young life as a sorceress and thief, stealing from Southwood’s nobility to survive. Now she must face the greatest test of her skills… A killer has struck Southwood, claiming the lives of nobles. Lord Kerim, Reeve of Southwood, turns to Sham for help... moreFrom the #1 New York Times bestselling author of the Mercy Thompson series (Frost Burned, Night Broken) and the Alpha and Omega novels (Fair Game, Dead Heat) Sham had spent most of her young life as a sorceress and thief, stealing from Southwood’s nobility to survive. Now she must face the greatest test of her skills… A killer has struck Southwood, claiming the lives of nobles. Lord Kerim, Reeve of Southwood, turns to Sham for help. Posing as his mistress, she delves behind castle walls to find the killer. But this murderer is no mortal—and Sham must use all of her magical wisdom to send the demon away. Because the city of Southwood has nowhere to hide—and no time to run… less

Shapeshifting mercenary Aralorn leads a dangerous existence. Now she must return home for her noble father, the Lyon of Lambshold, has passed away. But when Aralorn and her companion Wolf arrive, they find he's not dead, but ensorcelled by the ae'Magi, using him as a conduit to destroy Aralorn and Wolf. She must overcome this mysterious mist or fall to the blackest of magic.