/cgl/ - Cosplay & EGL

Hello! I was wondering what would be a good way to get the shape of Reaper's Halloween skin collar. It seems pretty rigid so I'm not sure if just using interfacing will keep its shape (unless I do multiple layers of interfacing?). I'm not sure what fabric to use for his costume yet so I'm not sure about the weight of the fabric and how that would play in. Right now I'm looking at some pleather fabrics at JoAnn's. Any help would be appreciated!