Stoma bags
It would probably be good manners to conceal the bag so that its contents aren't visible. While most of the people I've met would probably be tolerant of your conditions, they would probably be grateful that you took their possible queasiness into consideration.
I can speak from first hand experience! The stoma bags I got were always the solid colour, not the transparent ones that would basically solve your problem. I would agree that you would want to have a bag cover I dont think very many people want to see whats coming out. For me, I had a j-pouch surgery two years ago and that summer with my (four-month) temporary ostomy, it actually made me MORE courageous to get nude at the beach to promote ostomies. Now that I have only a big scar, its more normal looking and Im just another nudist. So, good for you for being a nude ostomate! But try and get the solid colour bags, since theres no difference in cost (at least in Canada).