I suppose the "cracks" in your eyelids/nostrils/mucous membranes that aren't covered by clothing or paint still suffice for the spirits to get through? But that doesn't make sense, because most of the body's mucous membranes ARE red, at least on Caucasians...

Let's not get into the relational physics theories of the thing, lol. WHAT ABOUT IF A PERSON IS COLOR BLIND, WILL WRAPPING THEMSELVES IN NORMAL DUCT TAPE WORK?