a person who is keen to get his hands, tongue, knob etc into a nice bit of beaver at every and any opportunity
Look at him! he's right into her pisher like a fanny rat
by Big Assed Ray February 4, 2006
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an un-used tampon
"Ahh gash, the painters are in, anyone got a spare fanny rat?"
by a joker April 7, 2009
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