There are two holes under the tail of the female cat. These two holes are different organs. The hole above the tail is the anus of the cat, which is used for defecation. The hole below the anus is the vagina of the female cat, which is the reproductive system of the female cat. The organ is used for mating and producing kittens. This is a characteristic of female cats. Owners can distinguish male and female cats based on this difference.