1 definition by Just some fuckboy

The act of using a female's period blood as lubrication while fucking them in the ass.
Bro 1: Yo brooo did you see that chick I had over last night?
Bro 2: Yeah bro did you bone her?
Bro 1: The red river was flowing, had to take the dirt road home through a blood bog.
Bro 2: Oh shit.. Nice determination - She had a killer ass.
by Just some fuckboy October 18, 2017
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