It is unlikely that the use of the noun "penis" as a verb is unique to #gaysf; however, Number-6 is by far the #gaysfer most closely associated with the verbification of "penis" on our channel. In fact, the origins of penis as a verb are in another channel...
During Number-6's self-imposed exile from #gaysf (where he was formerly known as Silly; see: cabbages), he was still active in channels like #unix and #freebsd. It was in #freebsd that Number-6 began to use "food" as a verb meaning to eat, which led to "beer" as a verb meaning to drink. From there, it was but a short leap of linguistics to "penis" being used as a verb meaning "to have sex with".