He feels an open summons and lets it grab him -
"Oh, go ahead. If nothing else, I can mount them on a plaque and stuff them in the attic."
appears his wings, dusky blue, five-"fingered" and spread out to full fourteen-foot span, and the tail, which goes down to his knees and ends in a tidy little barb, matched in color. He does a turn, and folds the wings (the tops go over his shoulders neatly), and wags the tail, and sits back down again.
"That feels much better. You wouldn't believe how accustomed I've gotten to the extras. I didn't even add the tail until a few decades ago."
"Well, I'm sure we can arrange for you not to have to go without them for too long on the way to Komarr."
"...but somebody has to do it and the list of people trustworthy enough to handle it and modern enough not to mind the wings and tail is full of people busier than I am," Miles finishes for him with a sigh.
"The idea that this is a modernity thing is very strange to me, coming as I do from the twenty-second century."
"If you came from our Earth you'd be at least somewhat more prepared for our planet's tangled history."
"From what I've been able to gather, the timelines didn't diverge that much until well after the date of my death. Anyhow. I will not suffer terribly from being a wingless tailless creature whenever this is convenient."
"Right, but you still need someone to generally interface between you and people who aren't prepared to hear that you're a magical demon from another universe, and that person might as well be someone who won't mind the optional anatomy. Hey, Gregor, can I steal Ivan for this?"
"I just have the feeling it might be handy to have someone around who'll do what I say without fussing too much. In case of Komarrans who won't touch me with a ten-foot pole, or whatever."
"He'll probably make some stupid remarks, but he won't run away weeping or start a riot or try to shoot you, and I expect he'll get used to it soon enough."
"My understanding is that getting all the way to Komarr takes a while, so whenever's convenient for my escorts, I suppose, I'm excited about the project but I've waited this long. In the meantime I can give somebody a crash course on generic summoning in case you want more than one demon's worth of magic done. I'll help you pay the fairies and angels if you like."