WitchCurse by Lissa Kasey

A kitsune, caged in magic; a child turned warrior; and a broken wolf, seek a chance at freedom, power, and love.
Kiran was captured and cursed by the fae to keep him from destroying their world. Nick was a child when he was ripped from the mortal realm and found himself trapped in Underhill. Bound together for survival, the duo never expected to escape into the human world. Toby, broken by the change from human to werewolf, finds himself drawn to the fae prince, and his rescued mortal servant.
The few remaining fae want the power of a kitsune at their fingertips. With Sebastian out of reach, the scattered courts are scrambling to cage Kiran and use his magic to fuel a resurgence. But Kiran is like all foxes, clever and determined to survive, even if that means binding himself to a broken wolf.
Can the trio find a way to unlock and harness the chaotic magic, protect themselves from the fae, and strengthen the bond forming between them?