Newbie - A corset is a back piercing...or more appropriately a set of piercings. There's a series of ring like...rings...through which a lace or ribbon is ran through, giving the appearance of the back portion of an old Victorian corset. I had an ex who really, really wanted one...lol didn't have the heart to say I wasn't a fan, given her enthusiasm (plus it's not really my choice anyway) and things didn't last long enough for it to have become much of anything.