"I got a great deal. Nothing doing on corporealizing ghosts?"

"Reviving the dead is generally believed to be beyond the power of magic.  How did you manage it? The rumors going around are so outlandish I can't work backwards to the truth."

"I'm from another universe, this is just part of how it works there."

"Another universe! I think that might actually be stranger than the rumor that you sold your soul to the devil for immortality and the ability to kill anything by looking at it. Pity our universe doesn't work that way."

"How would the devil expect to profit from the soul of an immortal person?"

Ghostly shrug. "No idea. I didn't spend much time on religion even when I was alive, and there doesn't seem to be a point to it now." He shakes his head. "Students here will exaggerate anything. The number of people I've heard being accused of secretly being dark lords just this past year . . ."

"Well, this year may reasonably have been exceptional, there was a cursed artifact possessing at least one person."

Slight, careful nod of acknowledgement. "So, if you are from another world, are you planning to return there? For that matter, is anyone else from your world likely to come here?"

"There is no immediate plan for either but it could happen! Why?"

"Just trying to get a sense of what to expect. Your world must be very pleasant, if people become magic instead of dying."

"People only become as magic as I am if they summon magic beings like myself to the world of the living first. If they don't do that, they still remain corporeal, and they get to be indestructible, but they don't get additional powers and wind up in a realm called Limbo, and you can't get summoned out of Limbo."

"Ah, so that's how you ended up here? I don't think anyone has tried summoning ghosts, except by means of mailing us invitations to things."

"...mailing you - how do you open your mail?"

"Well, if it's from another ghost it's on ghost stationery and then it's easy, but if it's on regular paper I can generally persuade the post owl to open it. Not that I get a lot of mail of either sort."

"The post owl."

"They're very clever little beasts."

"I guess they'd have to be. How is it ghost paper can be written on but ghost heads can't be completely severed for your posthumous convenience?"

"You know, I'm not sure. Perhaps it has to do with how killing parchment is more complicated than killing a person."

"That... sounds weird but a lot of magic here sounds weird to me and I don't have a better guess."

"Well, you're in one of the best places in the world to learn about it!"

"I suppose so!"

Sir Nicholas doesn't have much else to talk about; he makes his farewells and drifts off. 

Cam heads back to the library to look up post owls!

Post owls are sort of taken for granted by a lot of books; they tend to assume the reader is more interested in breeding them or handling their medical needs than with how they work. But he can learn that they carry mail and packages, have a magical ability to find any person or address that hasn't been magically hidden from them, and are intelligent enough to understand simple instructions like "get paid this many of this kind of coin before letting go of the package" or "wait for a reply". They're stronger and more resilient than nonmagical owls, but larger deliveries can still require a team of up to a dozen working together. International mail is often sent as a series of nested packages addressed to national post waypoints, where they can be passed on to another owl and where the first one can rest before returning home.

Golly. What an incredibly stupid and charming mail system. He looks at one of the books about breeding them in case it explains whether you need to cast spells on them or if they just hatch that way.