The smell of funky piss in organic matter. Pee that has not been shaken off properly or strewn about near the toilet. Once it has seeped in to organic matter (carpet, tiles or underpants) then continually worn or not cleaned for a long period of time.
Did you smell that dude? He smelled like straight piss rot.

These bathroom tiles smell like piss rot.
by AJ Elkenstein October 28, 2016
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