A fork of Rural Dictionary
When a girl sits down and her thighs expand.
Person 1: "She looks so thicc when she sits down"
Person 2: "Yeah that's cause of that sitty ploppy thing"
A ploppy toppy occurs when you're plopped down at a slot machine aggressively slamming the spin button in an attempt to hit the jackpot while getting a blow job either from a stranger or prostitute who may or may not be utilizing the Double Handed Gluck Gluck 3,000 method.
Oh man I was getting the gnarliest ploppy toppy last night from a girl of questionable dignity who I met at the bar near the sports book.