New age Cockney Rhyme slang.
Gary (Like Oprah Winfreys talking anus called Gary from South Parks 'A Million Little Fibers') is an english term shorted which should mean:
Gary Glitter - Shitter
I've just spoken to Tom he's on the Gary Glitter
shitter and will be out in 20 minutes.
Ow my Gary hurts after that Vindaloo dump I just took!