A. When the penis rubs against the toilet while taking a shit. This is mostly caused by a poorly designed lid.

B. When a turd drops forcefully through the water, scraping the bottom of the toilet where it leaves a streak.
What's wrong with your toilet man? I was hittin' porcelain while takin a shit.

Did you hear that loud Thoomp? Well that was me hittin' porcelain in your freshly cleaned toilet.
by BoLiverwurst March 26, 2008
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