FF The Runner Thief (The Chronicles of Arianthem III) by Samantha Sabian

Syn is a womanizer and a rogue. Her name fits her perfectly for she is indeed a sinner, flawed and unrepentant. She also happens to be the best thief in all of Arianthem, a career that would be most lucrative without her inconvenient attacks of conscience. She stays one step ahead of the Guild of Thieves, a shadowy organization that seeks to recruit her, and failing that, to stop her permanently.

Syn enters a contract with Raine and her dragon lover to steal a series of enchanted stones, but before she can even begin her spree she runs headlong into the roadblock that is the Lady Jorden. Jorden, a noblewoman far above Syn's station in life, pursues Syn like no other. And Syn, who has run from everything in her life, finds herself wanting to give in to those blue-green eyes and that wicked smile.