...both, I think? I can- well, they can touch me, too, when they're intangible to everyone else. So using me to cross from where it was trapped, to occupy the same space as other spirits-- when I said it went through I was being literal.

[One hand reflexively goes to his chest, as though there were a physical pang at the explanation; there never is, but the motion is entirely thoughtless, instinctive.]

It doesn't hurt unless it's forced, and in that case- it was crossing a barrier it wasn't meant to. Had to break through.