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Nightmare Fuel: Boy Meets World
Boy Meets World season 6 had the appropriately-named "The Psychotic Episode". As if the main plot of Cory having nightmares in which he kills Shawn wasn't bad enough, the subplot with Eric's new roommate could be stretched out into a full horror movie! The man keeps the corpses of his mother, uncle, grandmother and pet parrot around and makes them talk! Plus, it's implied he killed all his other roommates.
The flashback to Rachel accidentally destroying her stuffed rabbit in the garbage disposal is a bit unsettling.
Cory says in the last episode that Feeny hasn't spoken to another student in seven years. Knowing that the old, wise man has only been a help to simply the main characters and never actually helping (or trying to help) the rest of the student body through when they can be in a worse off place than any of the main characters we were watching all this time.