Usually meaning your extremely gay, or one of those fags that rides a harley, and can also mean that you have turrets and are painfully awkward.
Guy: Hey whats up*twitches*

Girl: WTF?

Guy: So you wanna get down and dirty?*(twitches)

Girl: Why the fuck are you twitching so much?

Gay as porter is typically shortened to "GAP"
by AldrichAmes September 19, 2010
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