When you have a muffin that looks as if it is a Turd that has been inflated with a bicycle pump.

It is usually thought of as a Delicacy in the eastern Society
Person 1: dude, that sewage mufifn looks epic
Person 2: dude, its not a sewage muffin, my mum made it,
person 3: HEY LOOK! SEWAGE MUFFIN
Sewage Muffin: Dont be crakin mah roflcakes nows,
by Decapitated Harlequin May 21, 2009
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