When a woman excretes menstrual fluids (blood) onto their partner. Such as a Golden show while the woman is on her period.
Danielle: I went to give Si a golden shower, but I juiced my vag blood all over him! RED RAIN BIZNATCH!
by Team Evil July 27, 2010
1 more definition
when you have a female on the rag drip the blood on you face
we were so horny she red rained on my head.
by Mikeagod March 21, 2005