Sideways Monster Mash Share definition Flag Used by Phillip J. Fry from the TV show "Futurama" to describe sex. Leela let's ditch these aliens so they can do the Sideways Monster Mash. Sideways Monster Mash by Zoidberg101 March 16, 2011 0 0 Get merch Get the Sideways Monster Mash mug. Buy Now — $32.95 See more merch
