Reluctant Witch by Melissa Marr

The Magicians meets One Last Stop in the sequel to Remedial Magic by New York Times bestselling author Melissa Marr!

After discovering she’s a witch and being whisked away to the magical land of Crenshaw, Ellie wants nothing more than to spend time with her new wife, Prospero, who has magically altered Ellie’s memories to convince her of exactly that.
Prospero herself is guilt-wracked after erasing Ellie’s memories and being forced into a sham marriage with the woman she loves for real. But Crenshaw is dying, poisoned by Prospero’s enemies who want their community to return to the human world, and she will do anything to save it.
The most powerful witch in anyone’s memory is in Prospero’s home, in her bed, with no idea that she’s a prisoner there… yet.
As the very fabric of their world is being destroyed, Ellie and Prospero must find a way to work together and save the world, and themselves.