Oberon

And this is why I love my job.

Mammilian Biology

So we had two black kittens for adoption, one male, one female. Siblings. Someone wished to adopt the male, and did so. Took him home. Called later. "I got the wrong kitten, I wanted the male. I seem to have gotten the female instead." We check remaining kitten in cage, verify that the female is still here. Reassure her that she did indeed get the male. She is quite insistent that she has a female kitten. What makes her so sure that the kitten is female? "Well, this kitten has nipples!"