When the male recipient of anal sex either doesn't achieve or loses his erection during penetration. As he recieves anal sex his flacid member flops around in a circular manner.
"You are so gay you watched that flop copter until it gained altitude."
"I was really turned on while she was pegging me but i was still spinning a flop copter the whole time."
"I was really turned on while she was pegging me but i was still spinning a flop copter the whole time."
by Mr_Hand November 7, 2009
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