When the scrotum shrinks to the point that it pushes the flacid penis up to appear as if it is a tiny boner, you have what is called, a shrinkage boner. Generally occurs during cold and/or wet circumstances, i.e. getting out of the ocean, pool, outdoor shower, etc.
I just got out of the pool and I totally have a shrinkage boner, want to see?
by Tommy_Z June 08, 2012