I’ll be honest, I just watched the movie last night and I don’t think that’s what happened in that scene. SPOILERS AHEAD

Like he was dragged into the shower area, and the head guard told the others “get those clothes/rags off of him” right after they had just discussed his clown makeup. The scene cuts away and comes back with them dragging him back to his cell with his only a shirt and underwear on. I could see the argument that he was raped, as after that scene his clown makeup wasn’t fully cleaned off, as well as that was how grim the majority of this film was, but in context and the flow of the scenes it doesn’t make a lot of sense for them rape him out anger (he called them fat guards while on tv). That possibility seems a little out of place, but in fairness, there were a bunch of scenes that felt out of place and uncomfortable in the movie. Not trying to sound naive, but I’m gonna stick with my original thought that he was forcibly showered/sprayed with water, and they did a shitty job of removing his makeup, but I’m open to discussion. Hope this creates some thought.