Skagunga 

NOUN
The putrified goo that comes out of a neglected, unwashed, moisture retaining objects, such as bath toys.

I was cleaning the shower and this HUGE glob of skagunga oozed out from under the shower door!!

Skagunga by Kurt Rodan September 20, 2023

spagunga 

As a noun, fecal matter. As a verb, to create such.

Holy spagunga, Batman!
You scared me half to death-I nearly spagungaed myself!

spagunga by Penny Pigtails August 19, 2008