Title: Across the Green Grass Fields
Series: Wayward Children #6
Author: Seanan McGuire
Regan is a completely normal girl. She has a loving family, a best friend, and she loves horses.
But then one day she steps through a door that asks her to “be sure” and finds herself in a world populated by centaurs, unicorns, kelpies and other magical equines, a world where human is synonym with hero. But not everyone feels that a hero is needed right now…