A friend to have a casual relationship with only for the purpose of filling a temporary relationship void.

Usually present in long-distance friends that choose not to have a long-distance relationship or friends that lead very busy lives and don't want the hassles of a full-fledged relationship.

An extension of a fuck friend
When visiting the West Coast, I'll get together with my on-call girlfriend for dinner & a movie and usually a night of great sex.
by Fukeneh82 March 16, 2005
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