The time of the month when female hormones wage a bloody battle against said female. An unfertilized egg that had sauntered down from the ovaries through the falliopian tubes and been stood up by its date, sperm, and the lining of the uterus become the refugees of the battle, and flee through the vagina, and on to the poor female's panties. Sometimes though, the female loses her war-ravaged mind, and thinking she can stop the misery, shoves a wad of cotton up her twat. This, like many peace-keeping efforts, fails frequently.
It was a period of strife.