Canine Vulgarity

Mr. Misha and I were sitting on the couch the other night watching TV. Both of the dogs were on the couch with us; the pug was nestled in Mr. Misha's armpit and the cocker spaniel was stretched out between the two humans. At one point, Mimi decided to stretch out and struck a pose much like this one:
Since her head was on my lap, I stroked her ears and told her she was a vulgar little girl. To which Mr. Misha replied, "She's just showing us her petunia."

In nursing school, I was told it was called a vulva....but forever more, it will now be known as 'The Petunia'.