A British phrase used to describe a promiscuous female and/or a homosexual male. Can also be used to describe My Chemical Romance's tour bus.
(on sight of a promiscuously dressed, knocked-up female:)
Person 1 'Look at that chav walking-sperm-bank slut. Belly like a fucking football'
Person 2 'A right penis buggy. Fuckin' pussy like a bear-trapper's hat'
Person 1 'And you would know how?'

(as My Chemical Romance drive by:)
'There goes the fucking penis buggy'
by WooForSam September 24, 2007
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