Cumgun Ask Urban Dictionary about Cumgun Share definition Flag The art in which you ejaculate into the barrel of a gun without any bullets and then shove it up your girlfriends ass and pulling the trigger. John: Yo i did a cumgun last night. Cumgun by Maxamoose7 June 19, 2019 0 0 Cumgun Merch Get the Cumgun mug. Buy Now — $32.95 See more merch