I love the kink you've got going here (one of my favs and I have some ideas as well) but I have to ask...are you exclusively m/m or would you consider an f/m scenario? I typically play only female characters in this type of kink, thus the question. NBD if it doesn't strike your fancy, figured I'd ask.
Re: m/m, feeding/stuffing without weight gain, belly kink, belly play/torture, big TW for vomit