A typical insult, generally used in disbelief at someones actions, behaviour or overall personality - think Paul Danan from Celebrity Love whatever!
No real origin other than that person is (or is being) a "fussy hole".
Can be used generically to insult people like words such as muppet, twat or dickhead, with the bonus that its not a bona-fide swearword so can be used almost anywhere at anytime.
"You're such a fussyhole!!!"
"Don't be a fussyhole"
"Paul Danan, he's a fuckin' fussyhole that boy"