1 definition by Fbook Masta

Butt-Sex Friday, a time-honored tradition started originally as a joke in the CU that has grown into a near ritual. Simply put, Fridays are set aside for buttsex, feigned or real, and anal activity is less frowned upon.
Cam and Udara had mad BSF last week-Zhe
by Fbook Masta August 13, 2006
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