This happens in mainly men and it depends on their genetic make-up and whether they are a hairy person or not. Yup, it's normal!
If you are a usually hairy person, then yes it is normal to grow hair on your butt. Dont laugh, I'm serious. Some guys and girls do grow hair on their butt, but mostly men. Don't be ashamed about it, lots of your friends probably have hairy butt's too.
i have a hairy ass at the age of 14