This commonly happens when you have anal sex with a woman over age 80. To have anal sex with a true Granny one must remove her adult Diaper. The Diaper will be typically soiled. Without cleaning the rectum,instead using the fecal matter as lube. The partner inserts his erect penis directly in the asshole of said granny. The result is a soupy brown liquid that runs from the granny's ass, the smell is said to be putrid.
Florence comes from television personality Florence Henderson, who is rumored to wear a diaper and gives Filty Florence's to many of the men at her Nursing Home. The rumor can not be comfirmed or denied.
Q. I heard that you like to fuck Old Ladies?
A. There is nothing better than Corn Blasting a Granny, the Filthy Florence smells terrible but turns ne on.

I was mopping the floors at the Old Age home last night and old granny Jones gave me a Filty Florence. It was so nasty that I puicked in her diaper.
by Granny Gromann June 3, 2010
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