In a hospital bed

You wake in a straw bed, a glass of water besides you. The sun has set and the only source of light was a small candle dimly flickering at the edge of the room. Near the candle you see a figure slouched back, resting in a chair with a book on their lap. The person snores and you become convinced that it is a woman. The feeling from the magic is strong here, but feels less stirring than right outside the cathedral. The woman stirs and you feel the magic fluctuate.

You get up and the sound of the wood floors creaking awakens the woman. She puts her book on a desk and rushes over to you. The anti demon magic intensifies, somehow it seemed tied to her state of consciousness.

"Sir, are you all right?" the woman asks. Her priestess's attire covers most of her body, she wears a black tunic and cowl. Only her face is fully visible and you recognize her as the woman who came for you in the cathedral.

"Sister, what is your name?" you ask her, more concerned with her and her connection to the magic than your own well being.

"Rosalind" she replies.

"Rosalind, may I hold your hand?" The priestess obeys your request and offers her hand. The instance your hands touch you feel a jolt of magic running through you. The magic wasn't just connected to the woman, it was emanating out of her. You hadn't the slightest idea how this priestess was the source but the strength of the magic on her skin was stronger the right outside the cathedral.

Now you just needed to figure how to disable the magic.

You notice Rosalind still staring at you and give her a small smile. You feel the magic permeating the room weaken as Rosalind smiles back. You were now sure that the strength of the magic was linked to Rosalind's mental state. When she was asleep the magic was weaker than when she was awake; when she was reacting to your smile the magic became blunted as well. If you could change her mental state enough the magic would weaken to the point where the demons could enter Wessen, or maybe the magic field would disappear entirely.

You gaze at Rosalind's book on the desk and recognize the cover. It was a collection of romantic poems, many of them erotic, a more scandalous book than a priestess ought to have.

"Sister Rosalind" you ask the woman. "I am feeling drowsy, would you please read me a story to help me sleep." You gesture towards the book.

"I am sorry sir, but I don't believe that book is-" replies Rosalind.

"Please, I still feel so weak from my fall today" you interrupt. The priestess stops arguing with you and skims through the book, trying to find chaste romance.

Rosalind begins reading the poem aloud and you curl up in bed. The poem tells the story of a knight who travels to a far land to escort his uncle's fiancee home, only for the knight and woman to fall in love along the way. Whenever Rosalind gets to a line describing the knight and woman's love for each other, her breathing quickens, her body stirs, and the magic flowing out of her diminishes.

Many of the women working as priestesses were left at a cloister at a young age. Poor Rosalind probably has never felt the touch of a man. The magic seemed to be connected to the purity of her thoughts, if she was tending to the ill or performing religious ceremony the magic emanating from her was strong. But the more she thought about love and physically attraction, the weaker the magic became. You just needed to corrupt the priestess and the magic field would fall. You grin, you knew you were going to enjoy the next part.