"A button freak"

Button freak? The hell is that? I've heard of a lot of different fetishes but I give up, I'm not sure what this is. Anyone care to explain?

Anyhow, I saw this movie the other day for the first time and I thought it was pretty good, I'll give it a 6 out of 10. Jane Fonda was definitely the star of the show but Southerland did pretty good too. Pretty good little flick, parts of it seem to carry on a little too much for me. In fact, imo some scenes should have actually been cut but I don't want to go into a lot of detail.

What is a "button freak" anyway?