Derrived from the derrogitory term for a disliked woman, and the slang word for a woman's menstrual perid, Cunt Rag is loosely used as a replacement for "Tampon". It is implied that the tampon has been used, and the said tampon is soaked with blood, meaning that whomever is called a Cunt Rag is the lowest of the low.
So-called as before the advent of sanitary napkins in the 20th Century, women typically used rags to control the flow of menstrual blood during their periods.
Can you believe it? I told Brenda I was going out for a six-pack and she has me pick up a box of cunt rags!