Possessed by Ava Thorne:
 
In a city where women burn daily for the crime of knowledge, loving a witch's daughter might be the greatest heresy of all.
 
Katharina is the daughter of a burned witch, raised by the Church that killed her mother. She secretly continues her mother's healing work while her guardian, Father Heinrich, shields her with his silence—even as forbidden feelings grow between them.
 
But when a moment of weakness on Beltane breaks Heinrich's sacred vows, something ancient slips into the cracks of his shattered faith. What enters him transforms his protective love into dark obsession.
 
Now Katharina must navigate not only the Witch Bishop's increasing suspicion, but the unholy devotion of a man who may no longer be entirely human. Is this the devil wearing her guardian's face, or the man freed from the chains of religious repression?
 
As Heinrich's obsession deepens and his shadow grows hungrier, Katharina faces an impossible choice: flee from the only person who ever protected her, or surrender to a love that might damn them both.