When you go down on a girl while she is standing and latch/munch/bite her clitoris causing her to flail her arms around like a Flamingo
James: Last night I was so pissed at my girlfriend Kimmie that I bit her clitoris and she acted like a Flopping Flamingo!
While fucking, you flap and flop and throw around your arms like crazy; like if you were at a big time rush concert.
Hey Shawnquel, I wanna flamingo flop you so hard! harder than a XXXtentacion concert!