STFIU-verb-meaning, stay the fuck in you.
mainly used in sexual intercourse.
"I want to STFIU"

STFIM-verb-meaning stay the fuck in me. also used in sexual intercourse.
"You want to STFIM"
"I want to STFIU"
"You want to STFIM"
"We both want to STFIU/STFIM
by Marcus12345678910 February 25, 2009
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