Malignant Monster Share definition Flag A big fat, smelly penis, even cancerous or diseased etc "The guy's a sad act, he whipped out his Malignant Monster on me again, this time it was dripping with smeg!!?" Malignant Monster by BorrisDancer November 4, 2008 0 0 Get merch Get the Malignant Monster mug. Buy Now — $32.95 See more merch