Gilch Share definition Flag When a guy ejaculates onto another guys gooch, and a girl sucks it off. "So, last night, I was invited to a Gilchfest. And now my gooch is sticky. Time to hit the showers." Gilch by Moses: Ruler of Mustardland February 18, 2010 0 0 Get merch Get the Gilch mug. Buy Now — $32.95 See more merch