Sheath for Toyota Prius keyfob

Every time I sit down or bend over or sometimes just take a step near my Prius when I have the keyfob in my pocket, one of the dadgum buttons will get pressed by a fold of cloth and the doors will lock or the alarm will go off, etc. I just got a 3D scanner, so I decided the first practical thing to make from a scan would be a sheath for the keyfob to prevent the buttons from being pressed.