Why are most of the monsters of the week female?

Why is it that most of the monsters of the week are females? Just starting with the episodes that are playing on Hulu, you would think the Dark Kingdom most of the yumas would be male, Queen Beryl gimmick was she was a domanatrix female that all these men working for her, all of her generals (not counting the DIC dub obviously) were male, so it makes sense all of if not most of the grunts were male as well. She was a woman of power that had men in a dominating position. And the coralans half of them should be male. Ali and An were the villains of the arc, one of a male and other was the female, so to represent them well half show some variety in the genders of their minons.