The excess sperm that is left on the upper lip after giving a really retarded blow job, making it look as if you have a mustache made of sperm. The word is kind of like a milk mustache but with sperm. Got Sperm?

Sperm Mustache Blow JobWiener Lip
*Damn Paul! Learn how to give good blow jobs, so next time you won't get a spermstache.*
by Jacob, Paul August 29, 2007
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