Why does everyone keep asking why they call it 'last'?
Its revealed in the first film that 'the last exorcism' refers to the last exorcism that the GROUP WAS PLANNING ON DOING & FILMING!
That's all. It had nothing to do with the main character.
"I'd say this cloud is Cumulo Nimbus."
"Didn't he discover America?"
"Penfold, shush."