"I wasn't expecting you to be especially repulsed...? And if I had an eye in my torso or something I probably wouldn't cover it up, that sounds like it would be uncomfortable. I do not have any eyes besides the two in my head."
"Same here," he snorts. "Just the two eyes." Pause. "... This would be so much easier if I were not horribly shy..."
"I have no idea, but I've never had to explain how mortals work um - physically before."
"Yeah. So I'm not sure where to start." Pause. "... Okay. Okay, I'm going to be an adult about this. Are you expecting me to have a um - a penis?"
"I was not forming expectations," she says. "But I'm familiar with the concept! So that's promising. So to speak."
"Okay, we're probably made from similar body plan - menus. There's some awkwardness over with."
"Is waiting for the discussed anatomy to be relevant a mortal etiquette thing related to the business with the towel?" wonders Promise, during a lull in kisses.
"Yeah," he says. "Also, I'm kind of - shy. So I'm maybe not a good example for all of mortal etiquette."
"Can you explain this etiquette to me before I accidentally upset you somehow?"
"You're not likely to upset me with it. Fluster me, probably. But not - actually upset without a bit more conscious work."
"I don't especially want to fluster you, either. Although maybe it's unavoidable if explaining would itself be flustering."
"Okay then. But for reference - when fairies have relationships with each other, usually, it's either part of an elaborate sort of game for each other's names, or they've already got a master/vassal setup and the master is doing whatever they like and the vassal might be more or less pleased about it. The part where I have fed you and am not giving you binding instructions more or less constantly is unconventional. So - I can be very little guided by convention here and it would help if I knew what background you were working from."
Is that a blush? Aww, look, that's a blush.
"You keep using the word vulnerable. How does wearing a towel make someone vulnerable? Vulnerable to what? For that matter, what power do mortals have to distribute?"
"Vulnerable to - not anything bad physically, but - judgement? Um. Appearing to not be prepared and having other people think badly of you or see things that you didn't want them to see. By power I don't mean the ability to do terrible things to each other, but things like, where they go on dates, plans for the future, uh - that sort of thing? I'm kind of bad at the specifics, I haven't been in a relationship besides - uh, with you."
"It would seem to me that if people who are trying to have a nice balanced relationship cannot agree on where to go on dates, rather than having to exercise any form of power about it, something is already the matter."