A fork of Rural Dictionary
That act of licking a girl's asshole (missionary) while she is menstruating.
The Dirty Rudolph
"She told me she couldn't have sex because she was on her rag, but I still went down on her Dirty Rudolph style..."
Sit on someone's face with their nose in your asshole, and twist your body side to side, leaving brown marks on their nose.
I'm def gonna give Donna a dirty rudolph tonight.