When one member of a couple (usually the girl) proposes an unnecessary temporary ban on any sort of physical contact.
1)
Marie: Marc, I think we should not make out for like a month.

Marc: Aw, girl, you're putting me in a sex fast?!?

2)
Roommate #1: Dude, why have you been so testy lately?
Roommate #2: Dude! I haven't gotten any love for like 2 weeks!
Roommate #1: Dude, why not?!?
Roommate #2: Dude, Lauren thinks it's a good idea to take a break from the touchy-feely for a while.
Roommate #3: HAHA! Sex Fast FTB!!!
by A-Street Boyz January 25, 2011
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