Someone who accidentally rats out someone during their usual stupid rambling conversations.
“...and then we were all at the bar, and Misty looked hot in that dress and everyone was looking at her. Then Laura blew a guy in the men’s room but, oh my god, this guy bought us all shots and then..”
“Wait, so Laura cheated on her boyfriend.”
“Oops, I wasn’t supposed to tell anyone” mumbled the Ratty Cathy.

No one ever told Clayton anything because he turned into a ratty Cathy after just one drink.
by Brett Burkhardt April 27, 2008
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