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1.
Substitute Sliding Fuck Buddy Friend. For when your fuck buddy is on her period or sliding and you need a substitute.
Squeak: "I thought you were only fucking Valerie?"
Spiderman: "No Valerie is my main FBF but when she's on her period I sleep with Helena. She's my SSFBF."
by Maddie 6 December 14, 2009