For weeks you've been tormented by nightmare, and have woken up sore and bruised. You've now learned that you're being haunted by the Mara, a night-demoness who flies into your cabin at night to "ride" you. If you can close all opening after she's entered, you can trap her in there with you, and even turn her back into a moral girl if you say the magic words "Mara Mara Minne".
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Uses the A/N script.
Uttering the magic words "Mara Mara Minne" will turn the Mara back into a human girl, and cause a personality change, by automatically changing the A/N. I might update the script to let you change her back, if anyone would want that.
I recommend diligent use of the /story action and Memory to keep track of the scene and reinforce the Mara's current state and personality.