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2.
Cock suckin-but fucker
He's a CSBF!
Man...what a CSBF!
I bet hes a big CSBF!
by "Jim" September 19, 2005
 
1.
Casual Sex Between Friends
Kim and I were friends since childhood. We never thought CSBF was wrong, since we were both OK with it.
by Andy Jenicek January 19, 2006