When a man cums in the reciever's eye, after engaging in anal sex, but leaves little chunks of poop in the reciever's eyeball, making it look like there's rust in their eye.
Guy 1: "So, Kim and I were fucking last night, and she wanted anal. So I gave it to her and I busted a nut right in her eye, and there was a little piece of shit in her eye after that"

Guy 1's friend: "OMG DUDE LOL RUSTY EYEBALL!!"
by K. Blaize February 7, 2009
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