Cam is dipping a grilled cheese sandwich into a bowl of tomato soup when he feels the summons. He goes ahead and grabs it. Doesn't even drop the sandwich.
"I try. Everybody is lucky Mr. Sacrificing People To Something got me instead of some more antisocial demon."
"Incidentally, don't draw on the floor, since apparently that can get you demons even though this is the wrong universe. I'd offer to teach you to safely summon things but it's not entirely clear yet that it'll work normally - say, if I can't get back - and I can't think of anybody I want to make that experiment with."
"Oh, no, I have no pressing engagements in Hell. I won't have the slightest reason to experiment with sending me back until the next concordance, and that's not for years, and that's assuming time is even passing at the same rate in both worlds and it hasn't been seven hundred years. Hell is perfectly nice, but nobody needs anything there and I can re-make all my stuff and I didn't have a close social network."
"It's when any pair of the non-mortal worlds overlap. Mortal world doesn't participate, but when Hell overlaps Fairyland, say, we get to send mail."
"I have penpals but not a close social circle in Hell. There are people who know me and we like each other for the most part, but I take a lot of summons and I'm pretty introverted and my old violin teacher and library buddies and so on will think nothing of it if I'm gone for a few decades, the pen pals will notice first."
"I sense you have figured out why I picked violin when I decided to learn an instrument."
"And I thought I was so creative. But anyway, I have a few violins back home and which one or ones I make here will depend on the circumstances."
"My kind of demon can't actually do that but it's a popular myth that we can. Yours can pull it off?"
"What happens to people with their souls stolen, and how does the transaction in fact occur?"