@roger,
Apparently he's based on a real person, a presenter of local news in the North East who inadvertently swore a few times live on air.
That's why the profanisaurus, which is now in it's 7th or 8th edition, is accredited to Roger. Readers of Viz write in with their own profane words and phrases, the good ones get published in the comic, and then make the next edition.