Book "All Your Perfections" by Colin Hoover

Mariana Andros is a brilliant, yet complex and contradictory group therapist. Her attention is drawn to the "Virgins" when the body of one of them, a friend of Mariana's niece Zoe, is found in Cambridge. Mariana once studied at the same university. She quickly realizes that the idyllic beauty of the pointed towers and the ancient traditions hide something sinister.