fuckbag Share definition Flag An artificial vagina used in prison. Its made of lotion or vasciline in a plastic baggie wrapped in a washcloth. Used for jerking off. I had a good jerk off last night in my fuckbag. fuckbag by thorshank May 11, 2015 0 0 Get merch Get the fuckbag mug. Buy Now — $32.95 See more merch