Keltham tries to figure out how he'd feel about telling the Chelish government - well, not to give him Carissa or else, because, like, that is stupid on so many different levels both as decision theory and as a trap that Isidre could be setting for him if she was less than absolutely trustworthy. Please give him Carissa permanently or until he gives her back, to do with as he pleases, and have that be the regulation of Cheliax and not just an arrangement between the two of them, formalizing what Carissa gave him informally, as Carissa herself wants according to your very smart people; and in return Keltham charges Cheliax very very slightly less of their GDP increase, or some such.
It's not - particularly landing, at this point?
In a world with Pilars, Keltham can see, somehow - not with the eyes of dath ilan but with the eyes of his own sexuality, that had no place available for it in dath ilan in a way that wasn't anyone's fault - Keltham can see how there could be a submissive!woman gender-subtrope that is like being pursued and dated, but more so. He can imagine how that gender-subtrope of woman might think it was more romantic for a man to desire her so much that he came in and just took her away, paying costs to do that but never asking. The question of how this ends up with the right people matched, and without giant flaming obvious incentive problems if a man likes a woman who doesn't like him back, may perhaps rest on Golarion institutions unknown to him; or it may be a reason why this desire unsatisfiable in reality is fed mainly by Golarion romance novels.
He can imagine that Carissa wants that - even if he's pretty sure he's not imagining it correctly, true to the real Carissa Sevar, it's enough to explain why a possible person would want that. To be in - metaphorical bed-chains, in her larger social and legal situation, chains that she wears always, as proof that a man wanted her that much.
Carissa wants it, let's suppose that to be true; does that situation appeal to Keltham himself?
...not really. The part where Carissa gives herself to him feels deeper and more meaningful, to him, than that choice being taken away from Carissa so that Keltham no longer knows she's still making it. It's a choice that says Keltham is worthy, that he and his sexuality are worth so much to Carissa, that she has judged him and chosen him even though she could have had another, that he is valuable to Carissa in a way he was not so valuable to any woman in dath ilan.
Is there some way you still get that in full measure, if somebody is with you because they can't escape within Golarion and have opted not to escape to the afterlife?
Keltham isn't seeing it, for now. Maybe his thoughts are being too crystalline and logical about it; too denying of subtleties and forcing it all into 'well, but then therefore' where people could just opt to not conclude that therefore. Maybe there is a way that Keltham can know Carissa still finds him worthy, even as she lives truly in the world where she has no other choice. Well. Like the Detect Desires spell, for example. If you have that around for people who can afford it, then it is obviously going to change some things -
SHIT.
Does Isidre do that to the people around her. Cast Detect Desires around them, or have it cast by a cleric who reports to her, and maybe not a cleric of Asmodeus either.
Keltham is trying not to believe it too hard, but his brain just shouted very loudly "YES SHE DOES", because Isidre knows far too much about what various people want. And it is extremely the sort of deontology violation that you'd expect from a Good person with a deficit of Law, an overly powerful intelligence headband, and horrifying problems that are horrifically large. Isidre would reason that the privacy violation was just not really that important, on the scale of twenty million people; and even if her intelligence headband lets her fake some intuitive shadow of the Law of Coordination, she might still argue to herself that knowing more true facts about somebody is not something that ought to cause a breakdown of coordination. Keltham isn't even sure she's wrong, he doesn't have her problems. Call it 75% probability.
But suppose Carissa is fine with Detect Desires being used on her. Though, maybe that aspect has to be illegible so Carissa doesn't have to admit to herself that she could escape by wanting to be free... well, leave aside the deontology violation of doing it without asking, suppose the thought experiment anyways. Or maybe Carissa says Keltham is entitled to Detect Desires her and truthspell her whenever he wants, because that is part of what it means to give herself to him, and they never have to make mutually legible why or whether Keltham is doing that.
Consider that Least Convenient Possible World, for the argument against putting Carissa in a situation where the 'absolute-power' (Keltham thinks the Taldane word in Baseline) that Keltham has over her has been formally materialized and made real. The world where Keltham casts Detect Desires every morning, or multiple times per day because Least Convenient Possible World, and the spell always says that Carissa still wants him and judges him worthy and would have him hold 'absolute-power' over her.
Then what?
Then Keltham does not really see the added appeal from his perspective; but it is not obviously, or not legibly obviously, something he couldn't do for Carissa to make her happier, at little cost to himself.
Except for where his mind just screamed that he is tilting further on that dangerous narrow ledge he is standing upon. And also, Isidre warned him not to have that done to Carissa unless he wanted it for himself.
Keltham doing it because Carissa wants it is probably not what Carissa wants either. The Golarion woman's romance novel is about the man who wants you that much in that way and not because he thinks it is something you need to be happy.
Maybe someday Keltham will come to feel for himself the thing that is the male complement of the gender-subtrope that Carissa has, where he wants for himself to make that 'absolute-power' real, and cast Detect Desires as a guardrail around it, and make it so that if Carissa can't stop wanting him then she can't stop having him either. Maybe someday he'll understand better the grounds he stands on in Golarion, and it will no longer seem like something that would get you kicked out of most cities in dath ilan... well, no, not actually, they're just not going to do that to you in dath ilan, if Carissa is standing there saying 'get the fuck out of our private business, Civilization, I don't need you to protect me'. No victim no crime, as the proverb goes. So it isn't like that. But maybe someday it will stop feeling like that.
Also Civilization would... what would they even think of a situation where Carissa is going 'Let me out, Civilization, I don't want to be here anymore!', to test the bounds of the chains placed on her and be reassured that they are real, and Detect Desires is showing that Carissa wants desperately for Civilization to laugh maniacally and say 'No you belong to Keltham now!'
Keltham is sad he will never get to subsidize this question in a voting prediction market. He really wants to know what Civilization would think of it. Well, no, actually he wants to see the enormous flamewar and Very Serious People shouting at each other that would happen if this question really came up. But also he wants to know what Civilization would think of it.
What does the Kelthamverse think of it?
...The Kelthamverse is, what, three days old, at this point? The Kelthamverse knows that it is a tiny baby world and wants to refer the question back to Civilization so that it has a good starting point.
But, mostly, this thoughtsearch has reached quiescence; there is not much expected value of logical information in searching further. Keltham finds no desire within himself, for his own sake, to transform Carissa's free gift to him into a metaphorical chain that she wears always; and for him to do it for her sake is almost surely not what Carissa wants. He will reopen the question when and if he finds within himself that gender-subtrope that is complement to Carissa's.
And meanwhile, he is not going to say anything to Carissa that sounds like 'Never forget, you've got the right to leave at any time!' because that would be stupid.