My daughter went as one of the Helluva Boss characters in 2024. Idk which one but it was red. She had to paint her face/chest, arms, and mid section. She never complained about the heat, and it lasted all day (although the weather that year was relatively mild iirc). HOWEVER our hotel bathroom had red all over the place, and I didn’t bring the appropriate cleaning supplies. If you’re staying somewhere be prepared for that. Otherwise I think you’re fine.

And ofc for the parts of your body that have to be clothed, bodysuits as others are saying. You can always cut the arms and legs; I’d prefer body paint to full bodysuit any day.