"I don't ....think a spell for that exists. You can't tell with Detect Intelligence until 12 weeks along. You could have some pregnant people in to Alter Self in front of you?"

Oof, that's a Cost there, if it has to be 12 weeks along, meaning they couldn't just find somebody who didn't actually want a baby and pay them to participate in the experiment.  Though maybe Cheliax has some wizards who only do the Alter Self thing after they detect, or change their minds, and advertising for one of those would turn somebody up... it doesn't really solve the main problem, though, because he can't be sure that what works at 12 weeks works at 1 hour.

"If you Alter Self immediately after sex, then shift back, would I be able to check inside you and verify that the semen had vanished?  Maybe I'd be willing to try for the further trust in that case, that semen doesn't persist in a vagina or uterus that you don't have... actually no, shit, I can't rely on that, because you could also produce that result with Prestidigitation even if it wouldn't ordinarily happen from Alter Self.  No wait, counter-2-arguendo, if you can cast Alter Self and come back fast enough, I can have Detect Magic running the whole time, check your vaginal contents before and after, and verify that Alter Self was the only magic to affect you over that period..."

This is actually kind of fascinating, as Compounding Capabilities problems go.  Maybe the eroLARP is deconstructing a computer game where the player needed to drag the spells from a list of available spells to form the correct structure to eliminate a pregnancy, before they could fuck anybody.  That sounds like how a computer-game version of an eroLARP would work.

Carissa has this job mostly because she is much less inclined than everyone else in Cheliax to throw up her hands at Keltham and go "MY DIAGNOSIS IS THAT HE IS AN INSANE PERSON" but she's sort of feeling that, right now. "I am willing to do that if you'd like it.

I ...think probably if we were secretly a Dread Empire we'd just mind control you about this, though."

"I appreciate and update on the argument; knowing as little as I do about mind control, or about how Hypothetical Bad Asmodeus might be concerned about my own god counterescalating, it's not enough to decide the issue.  Admittedly, if you carefully demonstrated mind control capabilities that can just completely undetectably to me make me believe or decide things, that would be a larger update than I've made so far about good Cheliax intentions; there'd still be the possibility you were in a balance against my god, but it'd be an update."

"Does that process give me the result I need to observe, on your prediction?  Detect Magic / check vagina / Alter Self / de-Alter / check vagina to verify that the process vanishes semen?"

“- mind control can do that. I don’t know spells like that myself but I would expect high-ranking palace security do.” What an incredibly convenient way to build trust, actually, have a sufficiently high level caster cast Suggestion on him and then promise that it hasn’t otherwise been done. Which it hasn’t because Asmodeus said not to, perhaps because it was worth it …

”And I think that process works.”

It's kind of complicated and tight, is the thing, for a poorly-tested process, he isn't sure that he can detect whether or not a vagina contains semen in the first place... but then it's basically backup against an itself-improbable conspiracy, not the primary means of birth control?

One also needs to consider that, at a sufficient level of magical power and ill intent, they could have done something clever when he had sex with Carissa the previous day, quickly moving semen from her mouth to her vagina, maybe as screened by an illusion.  Heck, they could've teleported sperm right out of his epididymis while he was sleeping in the villa the first night, before the Forbiddance went up - though they'd also have to mix it with seminal fluid to have a chance for the sperm to survive a uterus.

Keltham lets out a sigh.  "No promises, but I'll think about it, and tell you tonight whether to prepare Alter Self tomorrow."

Well that's progress! And on some level she can - respect how careful Keltham is, respect that while he does seem to care about her more than is healthy he's not actually an idiot about it, probably almost every Chelish teenage boy would do worse....

Well. Better to keep pushing. Lightly. "I prepare it every day. Hope springs eternal and also we haven't actually talked about exclusivity yet."

"I will... possibly maybe think about it faster, then, but this is security reasoning and can't be a quick decision.  And - exclusivity?  Like monogamy things?  I'm not quite sure what that has to do with intercourse."

"Well, see, I am expecting you to order me not to have sex with other people without your permission but absent such orders I might, you know, proposition someone who has an incredibly cool armored vest, and then want to have my Alter Self for that."

"Heh.  Point to you for catching me out on that, I think my brain is Assuming Things that have not been discussed.  If it wasn't just a more routine false closed-world assumption with respect to my ignorance of anybody else you wanted to have sex with implying that I was the only such person."

"I feel strangely like... there's a part of me that wants that thing to be true of you, that you ask my permission, but I also feel reluctant to give you that order right this instant and I'm going to have to do an introspection to figure out why."

"Incidentally, even if I can't trust it, is there anything way simpler and more standard that male fourth-circle clerics do to not have kids."

"Not that I know of. 

I wasn't - actually planning to go around sleeping with anyone else, knowing it bothers you, even though people here have really fantastic magic items. But I do keep a pretty sharp distinction, internally, between things I've agreed not to do and things I just definitely don't mean to, so if you want it to be the first thing we should talk about that."

"Super valid," Keltham says.

Not knowing any male contraception solutions for clerics seems so incredibly odd, to the point of being Suspicious.  Do male fourth-circle clerics who don't want kids just... not have intercourse ever, except with expensive second-circle wizard sex workers?  Who, going on earlier things Carissa has said, maybe don't exist in the first place?  Do female fourth-circle clerics just not have intercourse period?  Though it does match up with an earlier statement to him that YES PLEASE CHELIAX WOULD LIKE SOME CONTRACEPTION TECHNOLOGY.  Or, for that matter, that they (*cough*theEroLARP*cough*) didn't assign him any clerics in his research harem.

"I - I'm not immediately sure of where this internal resistance is coming from.  Some of it is coming from a source that thinks I'm asking you to give me too much and will then owe you something too huge and yes I know you already noped me on that.  But that isn't making the feeling go away and I think it's loud enough to drown out some other feeling, which means I can't just go ahead and ignore the combined feeling, and -"

"Is this an urgent question, for any reason?"

"No, it's not."

Actually, there's an even simpler solution.  "Until tomorrow morning, I order you to not have sex with anyone without my permission.  Whatever it is my brain thinks is scary about this whole deal, it doesn't think that one day of it is scary the same way."

"Understood. - and a good occasion for me to show you my other sex shop purchase." 

And she fishes it out of her Bag of Holding to explain.

Keltham is - intrigued, but can tell that he doesn't quite - understand, deep in this part of him, the shape he's looking at -

"But I could just order you not to do that, right?  Is the magic item for - people whose partners, in a relationship like this one, don't trust them?  I can guess that's not it, but I'm confused."

"That's not it - I mean, it's dispellable, so if I actually set my mind to getting around it I could. But some people enjoy the difference between 'impossible' and 'forbidden', like, you also don't need the chains because you could tell me to hold still, but if there are chains, then I'm not holding still because you told me to, anymore, I'm holding still because I can't move. Different flavor. ...also I think some people experience failures of will, about obeying an order like that for weeks or months, especially if you're messing with them around it enough, so maybe they actually do have to worry about breaking a rule even though they didn't mean to. I have never tried anything like this before so I shouldn't think too highly of myself but I think there's no order up to and including 'stick your hand in that fire and keep it there' I'd just disobey without warning you first that it was proving too difficult; if I would, then I'm just pretending, and I don't want to be just pretending."

He has again that sense of being unnervingly close to some ledge, on which Carissa may be trying to stabilize him, or maybe push him off.  His mind retreats from the dangerous thing, tries to talk about something lesser and more trivial and safer: oh, is this anything like the thing some women do in Civilization, if they want to have a lot of sex available to trade for social capital, or collect a large harem, where they limit themselves to one actual orgasm per month, and otherwise stop short of that, to increase their sex drives?

He forces himself to face the scary thing instead; it doesn't pay to do that all day long, but he's had relatively few shocking revelations today.

"I don't know whether I'm more frightened-intrigued by the notion of you wanting to make it impossible to disobey orders, or the amount by which you're trying to hand me the total keys to your sexuality, but both of those things feel like they're a step too far for me to do this minute, and I need to let it sink in for an hour without forcing it -"

"My mind is imagining you struggling inside the chains and not being able to get out, though, and it thinks that's very sexy, much more sexy than just being chained up at all -"

"I'm sorry.  I need to hear you tell me that's okay, if and only if that actually is okay, obviously, I'm not asking you to send a false signal, but even after hearing you say it's fine to kill you, my brain still wants to hear you say whether or not it's okay that I'd see you struggling to get out of the chains and not let you out."

It really feels like this is a situation that demands the ability to talk in metalanguage and say 'dequote'; but Carissa keeps on seeming to reject, not so much that specific proposal, as the entire framework of thought that would want to hear about it.

- okay, push the Keltham less. "I'm sorry. I don't mean to - rush you to the place you'll be when you're twenty-five. There's not actually any rush. It is definitely okay to be into me struggling in chains. It's - it is sexier, right, if the chains are actually doing something. And if I didn't happen to be into it, then I'd say 'it's a perfectly reasonable interest, I'm neutral on it' and you'd say 'reasoning with the mysterious Law Above The Other Law, one of the other girls will be into it', and that'd be all right too except for the part where it's very confusing. And if I happened to really dislike it then I'd tell you 'it is fine to be into that, but I dislike it'."

"I'm frankly going to be more than slightly freaked out if I find that the girls in the harem exactly match up to every single one of my sexual desires with no leftovers.  It would say some pretty unsettling things about where I am and how I got there."

"Uh, the reasoning that would make me worry about that is definitely below the Law, to be clear.  It'd be above the gods, below the math.  What would it even mean to be above the Law, I can't coherently imagine that.  Nobody gets to decide that 1 + 2 = 4."

"I notice my brain being a little tired of relationshipping, and it occurs to me that we haven't eaten breakfast and should plausibly go eat lunch or whatever's on sale... or free, I guess, since I still haven't gotten around to having any local money.  I should ask if this Governance location can use a channeled healing at whatever standard rates are on that.  But, I mean, we can also wrap up if you had any big important dangling issues, I'm not saying we have to go eat right now."

It only occurs to Keltham after he speaks that he just offered Carissa options and asked her to make a decision instead of providing info to him.  Is that even wrong?  He doesn't know, but that section of his brain may be tired and need to rest, maybe.

She seems unbothered. "Lunch sounds good. I doubt you can sell healing in the palace, even in wartime,  half the people here are clerics. Want me to go back to my room so you can have the afternoon to think?" Above the gods, not above Law. How could something be above the gods? It feels as absurd as deciding that 1 + 2 = 4. 

"Not sure, I'll decide after lunch."  A thought occurs to him.  "Oh.  And, Carissa."

"Maybe I'll rethink this order later, but for now -"

"You don't ask to be let out of the chains.  You can struggle in the chains, but you can't say in words, 'let me out'.  I won't flip out if you slip up and say it once, but if you keep on saying it, you'll be disobeying me.  Same if I hurt you.  You can tell me it's painful, you can advise me that a more experienced sadist in my position would probably stop, but you don't tell me to stop or argue that I should stop.  If I'm doing something to you that's going to break your ability to obey that order, let me know when you see it coming.  Understood?"

She is not sure where he’s going with that. But - “I understand.” And a smile, because she’s trying to reward steps in the right direction and that seems like one. 

Keltham doesn't smile back.  One conceals feelings, perhaps, but showing a smile you don't mean is quite a step beyond that; it destroys the ability to signal later, because how can anything mean anything, after that.  "Good," is all he says.

Keltham isn't at all clear on his own ability to ignore somebody asking to be let out of chains.  He doesn't particularly want to test it while he's still such a novice.

And more importantly, if Carissa Sevar does start telling him that he needs to let her out right now, Keltham will know that something broke her will to obey him and that something is wrong with the entire setup.

Maybe it's cheating to set up a secret completely legible meta-signal of meta-level failure, but then -

- cheating is technique, after all.

"Then let's go eat lunch," Keltham says.

(They get all the way as far as halfway to a small eating hall before Keltham notices a lingering confusion - though to be clear, they do continue walking towards lunch past this point - and starts asking why a single use of Alter Self doesn't render women permanently sterile, if it destroys their limited supply of eggs that have no analogue uterus to carry them in male form; and why an implanted embryo would be destroyed by Alter Self if the eggs weren't destroyed; and why men aren't rendered sterile by Alter Self during the week (or whatever that duration was) that's required to mature new sperm if the current sperm maturing in the epididymis get destroyed; and actually maybe they should try this with food coloring, if that's a thing here, to see if that vanishes permanently from a vagina that temporarily doesn't exist; rather than having sex that's potentially a security-premise-violation, if the whole method proves not to work the very first time it's tested.)

(Good luck, Carissa Sevar!  A dath ilani woman in your position would know exactly how this masculine gendertrope works, but you don't!)