This is accomplished when the one partener hasn't cut their toe nails for 8 weeks and shoves his foot in the other anus.
I met this whore down the street and i gave her a nasty old troll foot.
When a man doesn't wash his feet for a week and shoves his foot into the bitches pussy. Maaaaan.
"Dude I totally troll footed Kevin's mom last night"
"Maaaaan why you gotta be troll footing my mom?"