Don't want to spoil anyone's fun, but I would call this quite a clever piece of performance art.
fat-pie.com is the website of David Firth, who created Salad Fingers, which is quite a famous twisted cartoon done in Flash (Lots of people like it, I thought it dull - I'm sure someone posted it on here an age ago). He's a done a few other things as well, although Wiki still quite slim on him.
And as Devvo's creator is from Doncaster, about 20 miles from here, I'd say he's meant to be, or is, a Doncaster lad using a put-on Mancunian drawl as all these cunts have been doing since the late 80s. He certainly sounds like some lads in Scunthorpe.
The use of an isolated "fucking.." to fill in a pause in a sentence is also spot-on.
So Devvo is not 100% real, but it's not 100% fake either - there really are cunts who talk and act like that across the North of England.
[Notice which four letter C word I prefer to use to describe them...
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