Metalmuffin Share definition Flag A based individual who is so throughly themselves they have waton disregard for social norms to the degree most people find distasteful. Ruby was such a metalmuffin that she got blocked on social media. Metalmuffin by RMMD December 6, 2022 0 0 Get merch Get the Metalmuffin mug. Buy Now — $32.95 See more merch