Well, if I ever really get a chance to set up such a belly punching match I will primarily keep in mind 3 things. Those would be fixed. 1st, it will be by my wife's consent and full knowledge. Next two is equally important if not more. One, my wife should be wearing her dress real real low (dangerously low lol) and the belly slightly oiled up. But keep in mind that the dress should be something she is used to wearing so it looks real. Two, the match should be with rules but real, with real pinches and real submission, not fake. The pinch, pain and tears should be real.. so would be the submission.
Match will be by consent of both woman but real.
Rules would be there for protection, but it should be real deal and no act :-)