Sarah B.'s definitions
acronym for: secret internet fatty.
molly: omg that girl is huge!
tina: i saw her pics on myspace, i thot she was skinny!
molly: wow what a sif!
tina: i saw her pics on myspace, i thot she was skinny!
molly: wow what a sif!
by Sarah B. August 8, 2007
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