Thorn Queen, by Richelle Mead

Storm born Eugenie Markham is living a dual life. In the human world she is a shaman, banishing ghosts and other supernatural creatures that cause problems. In the Otherworld she is the reluctant Thorn Queen, trying to come to terms with her new responsibilities and her growing powers. Torn between two worlds, she is also torn between two lovers – Fox man Kiyo and charismatic Oak King Dorian. Eugenie finds herself drawn more deeply into the life and troubles of the Otherworld as the land needs her personal attention and she uncovers the mystery of young women going missing from small villages. Frequent and graphic sex scenes are tinged with BDSM but they are not included just for titillation. Mead cleverly juxtaposes the active sex life of her heroine with the central theme of power and consent.