A huge celebration when a Bill turns 17 and comes out of the closet. The celebration usually includes watching gay porn as well as participating in numerous mouse holes and other gay acts.
Bill: Man that gaymistfa last night was so crazy.
Bill: I know, i'm glad you came out, can't wait till Bill has his gaymitsfa.
Bill: I know, i'm glad you came out, can't wait till Bill has his gaymitsfa.
by quitdajibjab April 17, 2009
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