A vagina/anus that hasn't been cleaned for at least 2 weeks. Usually green, orange or reddish in colour or even in combination/mixture. Such mould boxes contain smegma or cheese, more STDs than a Liberian village and a rancid smell. Occasionally you can find frogs, cockroaches and mice if you tap it. Mouldy boxes smell like shit, blood, mould, 40 day old rotten fish and most McDonalds bathrooms. Mouldy boxes usually can be prevented/fixed with a regular shower however if times are desperate, use mould killer.
Jim 1: Hey bro, I fucked my girl last night and when I was eating her I vomited! That shit was rancid.
Jim 2: Bro, I bet she has a mouldy box! Bring mould killer next time or a plastic bag as a condom.
Jim 1: I think I smelt some swamp water in there too...
Jim 2: Was it Steph Woody?
by trickysamurai June 11, 2019
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