The (often surprise) discovery of a penis on a woman who, it transpires, is a transexual or, in the vernacular, a ladyboy.
Hey! Did you hear about Greg last night? He clicked with a Thai girl at the bar and when he got home with her he found she had a filly willy! Dude, was he shocked!
by Jeremyhotpepper June 4, 2011
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When youre shagging a guy from filbert village and they cannot get it up, due to the high amount of substances in their system (i.e. Drugs, alcohol).
"omg the guy from block e had such a filly willy"
by Bossman42068 December 3, 2020
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