The Eighth Road by Joss Walker and R.L. Perez

Haunted by memories of her mother’s dangerous exploits, Sofia Thorne is determined to keep magic away from her sister, Jayne, forever.

In a desperate attempt to permanently sever magic from their lives, Sofia travels with Jayne to Miami to track down a dangerous witch who might have a solution. But when they find themselves caught in the crossfire between two powerful magicians, Sofia must face her greatest fear.

Can she protect Jayne from the dark magical energies that killed their parents? Or are the sisters destined to fall victim to the same twisted power?

“Everything I love about urban fantasy: a wise-cracking heroine who diffuses tense situations with a joke, plenty of adventure, and an interesting magical world that exists alongside our own. I can't wait for more adventures with Jayne!”
—John McDougall, Murder by the Book