Is it normal to have a sex dream about someone that you can't stand?

I recently had a very vivid sex dream with a girl that I really don't like at all. She is nothing to look at. Her personality borders on cruel. And she is just a spiteful, small person. But there she was, in my dream, giving me some of the best sex ever!

And no, I don't secretly like her or have bottled up feelings for her. I seriously can not stand the sight of her.

Has anyone ever had this happen to them?