The First Witch-Mage by Isabel Campbell

Those who cross a Blackwood soon learn that they won’t like the results.

Theadora Kathryn Blackwood’s life is just the way she wants it. Thea focuses on what she wants to do, what she wants to study, and the local COVEN hierarchy leaves her the hell alone.
It took years for her to accomplish that much freedom, and now she is about to graduate college, the local coven leader has given her what she wants most.
The opportunity to be freed from the shackles of Coven Politics for the rest of her life.
The catch is that she must join the Arcane Investigations Division as an Arcane Consultant for three years.
If Thea is still employed at the end of the set time, the Coven will absolve her of all ties and responsibility to them.
The downside is that NOLA AID has lost two witches in the last four years. No one expects an untrained witch without the Coven’s support to survive.
Even if she is a Blackwood.