The strange dry, mildewy texture that occasionally accumulates on washing that has been left outside to dry overnight. Generally suspected to be the saliva and jizz of goblins and other such creatures of the night.
TIM: "Hey bro I'm just going to hang my washing out to dry before we leave tonight"

ALPHONSE: "Are you fucking insane you goddamned fool??? They'll get the Nightfunk!!"
by Dr Newmann Van Fock October 13, 2010
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