When a girl is on her period, but doesn't tell a guy before he goes down on her. The question being, "is she on her period?". The answer, "yes" and you found out when you tasted blood.
John: Dude, did you hook up with that girl last night?
Jim: Yeah man, but she pulled a Rusty Riddle on me, it was disgusting.
by CapD July 28, 2011
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