Only contestants appearing on stage (including cosplayers and ninjas) are allowed to be in the green room/backstage during the show. He flexed his muscles and flew circles around his parents to show me how fast he was. Show Some Love with Infant Halloween Costumes for Babies. One of the most excited fans was a little Superman, cosplay costumes proudly wearing his foam muscled outfit from the Halloween store. “Cute” doesn’t quite cover it.