Sheep-Goats posted:

Rare disorder!

"What little evidence we have suggests that someone formerly known to you has been co-opted by a malicious spirit and will soon come to you in the night, attaching itself to your back, running its thin inch long immaterial claws through your flesh, giving you every unpleasant sensation you would receive as if they were material, but none of the physical damage. The creature also reads lists of items it feels you might be interested in from catalogs unceasingly into your left ear"