One who will make false accusations about people and be unable to back them up.
They will convince themselves that the accusations are real, and will never admit that it was made up.
Peter Paranoia claimed that Joe was stealing all of his tools from his shed, then Peter Paranoia accused somebody of urinating in his chocolate biscuits and lemonade.
Anything unexplainable by science. Anything supposedly thought to be the figment of imagination which cannot be proved by scientific means. Extra terrestrials and ghosts fit into this category. There is no proof that either do not exist. If you have ever seen anything you can't explain scientifically, then that is paranormal by definition.