When you use a sponge as a cumrag and forget about it under the bed. Several weeks from then, mold will grow, fusing with the semen, forming a rust-looking sludge all over the sponge.
Person 1: Bro I found some good-ass porn but all my rags were used so I used my mom's dish sponge.
Person 2: You made sure to rinse that shit out, right?
Person 1: Nah man, I left it under my bed and now it looks like this *show sponge*
Person 2: Nigga that's a rusty sponge!
by TimmyTheSlayer February 27, 2018
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