Blood & Honey by Shelby Manhurin

Lou, Reid, Coco, and Ansel are on the run from coven, kingdom, and church—fugitives with nowhere to hide.
To survive, they need allies. Strong ones. But as Lou becomes increasingly desperate to save those she loves, she turns to a darker side of magic that may cost Reid the one thing he can’t bear to lose. Bound to her always, his vows were clear: where Lou goes, he will go; and where she stays, he will stay.
Until death do they part.