This was written for rokhal's prompt in the latest sharp_teeth comment-fic meme: "If Sam hallucinates being possessed, then for all practical purposes, he actually is possessed. Just a little more difficult to trap or exorcise."
... I ended up doing weird things with it.
Warnings: SPOILERS for s7 in general, violence, blood and gore, insanity, weirdness, metaphor-abuse, present-tense.
( Look, Sammy, it says. Look at what you are now. )