The Drujs are terrible demonic beings, mostly female. The ancient Iranians believed that they were the enemies of the asha, the universal law.
These are terrible creatures and should be avoided at any cost . The horrifying dragon Azhi Dahaka was a Drujs and so was Nasu, who used to settle on dead bodies in the form of a fly to hasten decay. Another Druj, Jahi, was the symbol of the evil within women. The spirit of darkness, Angra Mainyu, kissed Jahi and thus introduced the so-called impurity of menstruation to women.