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.
"Hello," the summoner says pleasantly.
The music is... weird. Instrumental, pretty, weird. He produces sheet music for it and the notation is very strange. There's a violin part, though. After he's listened to all five songs he starts trying to learn the violin part for Another Century. It doesn't sound right. The notation is really weird. He can't figure out what clef it's in or what some of these symbols between the notes mean. He can play the part more or less by ear if he tries, but connecting it to the notation seems like it might be a longer-term project.
"I didn't actually know the planet part," says Cam. "Although I would have guessed if I were more willing to assume that song lyrics referred to historical events, or if I'd invested more time in poking at your mysteriousness. I already added Ash and Stars to my library contribution but there's a chance nobody's picked it up yet; I can make a revised version and swear my lips are sealed if you'll tell me what's going on."
"Many things are going on. One of them is that I'm summoning you from a different universe than the one you're used to - if it's 2159 or 1995 where you're from, you're probably from a world I've at least heard of, but I've heard of two separate such worlds so it's not out of the question that there might be more. Another is that it has been decided by... let's call it an extremely informal interdimensional security council... that letting any daeva know about the existence of worlds beyond their current reach is to be stringently avoided on the grounds of potentially apocalyptic consequences. I'm sure I don't have to draw you a picture."
Cam conjures up a revised list, tosses it into the air once (it's rolled-up paper), and then tosses it a bit higher and sets it on fire. "List revised. 2159. But we're not the hazard. We can't move around on our own. It's those summoners from extra worlds you've got to look out for."
Benign and adorable.
"A personal project I cannot yet tell you about for interdimensional security reasons. But it's not out of the question that I might tell you more once I know you better. Now, on the other hand, I do have a secret project I could use your help on: if I were to offer you the design for a device to safely contain black holes, could you take it home and test it and successfully conceal its origins from other demons? I don't have one yet, but it's coming any week now, maybe any day."
"Yyyyes. Depending on how tight you want your infosec it might take me a while to get far enough into uninhabited void for nobody to detect my shenanigans, but yes. May I then pretend to have designed it myself so that demons in general can provide in my home universe if called upon to do so?"
"Of course. If you're good at math - and I mean really good at math - I can even provide you a couple of textbooks so that you can study up and plausibly pretend to have designed it yourself, but 5-space calculations are an enormous pain to anyone who is not passionately in love with math or physics or both. Anyway. Care to fill three more crates with two hundred thousand zorkmids each in exchange for my carefully curated song list? There's about thirty on there, from two bands and an orchestra."
"The person who helped me out with infosec, who was from 1995, didn't profess to any difficulty reading modern books - I thought it was a little weird that the language would've stayed so mutually intelligible with its past selves, but I checked and indeed it has, on which premise it's not that strange that I can talk to you. And no. They didn't warn me about the languages thing. What is the languages thing."
"It happens that I already spoke English or I would have had no choice but to use one of your accents, but usually when you get a daeva, in so doing you grant that daeva all the languages you speak. Prevents issues with someone who only speaks Martian Portuguese from getting an angel who was last summoned in ancient China and having a communication barrier."
"How convenient for you. Especially if you're going to listen to all the Barrayaran music with lyrics I carefully and pointlessly avoided giving you. Uh, some of Astra's Greek stuff gets pretty filthy, I feel I should warn you in case you don't like that sort of thing."
"My education on how to bind daeva went into great depth. I am also forewarned that there is no such thing as a soul, at least not for you. Relatedly, I have no education on gagging daeva, not that I want any. I have overviews of the three kinds of powers, but not details such as 'he can just conjure their entire discography anyway'."