Someone with whom you do not have a relationship with but you have mutual sexual relations . Usually using the abbreviation FB, although, FB is sometimes mistaken for Facebook or Finger bang .
Most of the time, both members of the sexual relation are single and their relation is strictly for only that purpose.
Ex 1 - Hey dude, I am going to hang out with my fuck buddy today
Ex 2 - Hey, I know this is sudden, but do you want to be my FB Fuck Buddy?
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