Sewer Mask Share definition Flag The act of spitting the tasty fecal residue of a tossed salad from your mouth onto your significant other's face. Chris finished eating ate Debbie's ass and promptly gave her a sewer mask. Sewer Mask by Pat Bateman April 26, 2005 0 0 Get merch Get the Sewer Mask mug. Buy Now — $32.95 See more merch