Making Body Pods

Hey guys, this is more cosplay related, but I was wondering if I could still get any input.

I'm kind of in a pickle about how to make a body for rotund characters such as Judd the cat from Splatoon.


I've seen studios like Lobitaworks that have used hula hoops beneath some sort of foam structure to keep the body stable and rounded, but I'm still overall confused? I was thinking that I could sew up some of the flatter upholstery foam that has a backing into the same shape that I plan to make the head out of with the green upholstery foam. Then I could slip it into a sewn faux fur body and it would just make it round out (perhaps with the help of hula hoops)?

I'm talking about the black stuff that some suit makers use for their headsocks:


Let me know if you have any inkling of thought towards this idea!!