Dirty Magic (Prospero's War Book 1)

MAGIC IS A DRUG. CAREFUL HOW YOU USE IT.
The Magical Enforcement Agency keeps dirty magic off the streets, but there's a new blend out there that's as deadly as it is elusive. When patrol cop Kate Prospero shoots the lead snitch in this crucial case, she's brought in to explain herself. But the more she learns about the investigation, the more she realizes she must secure a spot on the MEA task force.
Especially when she discovers that their lead suspect is the man she walked away from ten years earlier - on the same day she swore she'd given up dirty magic for good. Kate Prospero's about to learn the hard way that crossing a wizard will always get you burned, and that when it comes to magic, you should never say never.