This week, Katie eats the "nom nom" cupcake that is Two Twisted Crowns by Rachel Gillig, the second book in The Shepard King Duology (which really just devolves into some incoherent fangirl sighing at the end, because wow, this book was excellent?)
Two Twisted Crowns by Rachel Gillig
https://www.goodreads.com/book/show/63910262-two-twisted-crowns
For similar books:
One Dark Window by Rachel Gillig (Part 1 of the duology)
https://www.goodreads.com/en/book/show/58340706
Uprooted by Naomi Novik
https://www.goodreads.com/en/book/show/22544764
Belladonna by Adalyn Grace
https://www.goodreads.com/en/book/show/59227936