She's in a Mage's Private Sanctum. Her boyfriend is planning to murder her god. It had better speak up, whatever it is. 

This is approximately the most unpleasant-to-acknowledge possible reality, ever, in all of history, but - 

- if that's what Good has been playing for - 

- they've been helping her. They've been right.

Asmodeus does not make good use of the souls under His care. He does not make good use of the souls under His care because that is not His only value; He holds it alongside other desires, like for people to have absolute power over one another, the power to make them suffer excessively for no reason. You could have a Lawful Evil god of the words that Carissa spoke to Maillol, that she has a duty to make him stronger and not weaker, that her ownership of him does not permit her to destroy him carelessly for no reason -

- but that god wouldn't be Asmodeus. 

People don't want to go to Hell because Hell is a bad place. They are choosing Abaddon instead because Hell is a bad place. It is so hard to find ilani who can also be Asmodeans because if you have any other choices you shouldn't, actually, serve the god of being allowed to destroy your subordinates for no reason, out of incompetence or because it's momentarily funny.

Asmodeus sucks, and if not for the thing where He'll destroy the world if you try to destroy Him, Keltham would be right, to want to attempt it. 

If she does go to Hell and get all the paving stones to fix they're going to be - unimaginably worse than Maillol. And no one did that by accident because they sincerely believed that they had to learn how to torture people, they did it because they wanted to. 

It's not, actually, hard to see, not at all, not once you look. A little child could see it. 

Probably destroying people is bad, actually. Even if you don't have to look at them and talk to them afterwards. Even if you never have to think about them again. 

Nethys saw that Keltham, when he learned what Asmodeus was really like, would try to kill Him. And by default that would definitely be a complete disaster. So Nethys - and Cayden Cailean - have been carefully maneuvering to arrange terms that Asmodeus can accept, terms that are better than 'killing Asmodeus' for Asmodeus, and better for Good than - well, potentially they just have to aim for 'better than literally everything being destroyed by Asmodeus' -

- how could she have heard that story and not had her faith snap instantly, how could she have ever worshipped something that was willing to destroy the world -

Cayden's interventions all served Asmodeus in that they set up some compromise Asmodeus is going to be willing to agree to to avert a war. The compromise might in fact involve Carissa becoming a Power in Hell who does not destroy people, ever, even the ones she actually hates. The half-Wishes deal was better than the full-Wishes deal because it prompted Carissa to ask for the rights to those souls that seek her.

That's - threading an entire universe through the eye of a needle - but if anyone could do that, Nethys could. 

The reason Nefreti said she couldn't help Keltham in any way is that if Nethys just said to Asmodeus 'look, that there mortal is going to destroy you unless you accept our compromise', Asmodeus would check if Nethys put that mortal there to pull that off. It's important, that Keltham is not a cleric of Abadar, not assisted by Nefreti Clepati, that humans, alone put him where he is, because humanity wanted Asmodeus dead -

...the reason that Cayden was mysteriously working against Iomedae is probably that Iomedae is all in favor of Asmodeus being murdered, who cares if that destroys the world -

It all fits, it has a sort of terrifying clarity to it, a hundred puzzles reduced to only two or three, and she suspects those aren't the important ones, brushes past them mentally in the heady rush of realization. 

And it makes sense of greater-Carissa, who must have had the same realizations and then gone to work on -

She cannot, quite, fathom the courage it would have taken, to realize all this and decide that in order to enable a compromise she needed to go sell her soul to Dispater. She's....pretty sure Dispater won't be amused if she in fact dies and shows up party to a conspiracy to - well, technically she's not party to a conspiracy to kill Asmodeus, she's party to a conspiracy to force Asmodeus to terms so that Hell can be run by someone who won't destroy people, such as, for example, herself. 

Or maybe He'd think that hilarious. Maybe He knew all along. 

Anyway. Current leading hypothesis: Keltham got nervous when she went a couple of days without rederiving their plan and caused a scare so she'd get stuffed into a Mage's Private Sanctum so she'd figure it out. 

Secondary hypothesis: this was a genuine kidnapping/rescue attempt that went wrong somehow. 

Tertiary hypothesis: Nethys was steering for something even weirder and more hyperspecific than 'she rederives the plan'.

Evidence in favor of the secondary hypothesis: this is actually a fucking terrible time and place to rederive the plan. If she'd figured it out this morning she could probably just have bluffed her way out of the Forbiddance, no problem. But at this moment she is locked in a large iron box with three wizards far more prepared for combat than she is, only one of which is loyal to her and possibly would change his mind about that if he were aware that she was apparently a coconspirator in a plan to overthrow Asmodeus. 

Does she have some spectacularly clever way to kill three Security with the advantage of surprise and a lot of Fire Resistance but no other particular resources. 

....no, she really doesn't.  She's not a combat caster; she's not done preparing her spells, she's going to have fewer spells than usual, and they're going to be incredibly suspicious if she starts casting anything even slightly useful. 

....could she scrap her lesser artifact headband for spellsilver and make it into three Arrows of Greater Slaying, in the next couple hours, if she worked really hard on it. ....no. Quite aside from how intrinsically horrifying it is to contemplate destroying an item like this, and the fact it's probably only destructible by the will of Dispater or immersion in the Lethe or something, and the fact she'd still have to stab them with the Arrows of Greater Slaying, she could probably make one today if she worked at quadruple the normal crafting pace. Not three.

Keltham, did you have a plan, here, or was I supposed to get myself out of this one myself?

I have to say, Keltham, I think by any reasonable definition we're firmly into Complicated Romance, at this point. 

It's funny. Figuring it out happened all at once, in a moment of blazing clarity. And the first time, she must've had no time for anything after that, no time for - revulsion, or horror, or self-loathing, she was so busy working out the next steps of the plan, she had so little time in which to take a step back and look at anything - but now, the next steps of the plan require her to finish this here Teleport she's building, and it's not done yet, and so there's lots of time, to look back at it and really see it. 

She's awful. She assumes that it had to be her, for some reason, that Nethys saw a trillion trillion ways it could go and there wasn't a better one, but - she's awful. She wouldn't worship her. People do, but - only out of desperation, presumably, only because Asmodeus has set the bar so terrifyingly astoundingly low. There's not actually anything to worship. She was horrible to Keltham. She was horrible to Maillol. She was horrible to Peranza and the Security watching Peranza and the Security she had ripped apart and the Mayor and in every single case it was for nothing, it did not advance her goals, it was just that she thought she was supposed to be and she thought everyone would be impressed with her and so she did it. She was presented with peoples' lives, their eternal fates, their whole selves, people who trusted her, people who believed in her, and she decided what to do based on what would suppress her cognitive dissonance most. 

She isn't worthy to be a god. She kind of wants to curl up and be a paving stone until she's fixed except - it doesn't fix anything, does it, turning people into paving stones. Everything she said to the Mayor was true of herself as well. Incoherent, cheap, pathetic Evil, doing whatever happens to be in front of you, utterly devoid of principles. Selfish, hollow. Except she was wrong to think that Hell was any better. Less petty, maybe, but if anything more wasteful, because in humans there is the impulse against wastefulness, the voice that she's stopped listening to but that absolutely did warn her every time - and in Hell that is quieted -

It is kind of astonishing that Keltham agreed to keep working with her at all. Or maybe he didn't, and Peranza and Asmodia were his conditions, maybe he told her to go sell her soul if she really wanted to start making things right - she'd have done it -

(Somewhere, distantly, she notices that actually her thoughts are still not adding up, that she's missing something important. Much less than she was missing ten minutes ago, definitely, but - enough to potentially be consequential.)

Whatever it is she will probably figure it out once she's not trying to simultaneously prepare a fifth-circle spell and keep her face totally unreadable to three observers who are on edge and have very good Sense Motive. She suspects that's kind of cramping her style. 

It doesn't really feel very like Keltham, to order her to sell her soul and then after she erased the memory of the conversation order her not to. Obviously she wasn't going to listen to him, but still. It's a weird order to give if you think she's obviously not going to listen. 

It also doesn't feel very like Keltham to not just kidnap her last night. Well, probably Palace security's pretty good, but this situation merits a Wish-kidnap and at minimum she could've been grabbed while leaving Avernus.

Is it possible she - wasn't coordinating with him? 

....in that case he is probably terrified of whatever the fuck she's doing. 

Just give me twenty minutes, Keltham, I'm coming.  

...she's now unreasonably upset that Maillol isn't going to get his vacation on account of her defecting. She told him he'd get it. Of all the things to find upsetting about having realized that she needs to overthrow her god before her boyfriend tries to kill Him. 

....maybe she can fix that. It's not the best possible trade of credibility for results, but - but she feels like every single fact about the world she could point to as a fact about who Carissa Sevar is, right now, is a sickening and horrible one, and - she can't just -

"If we're going to be in here a while, I request this morning's communications from Egorian, read out to me if that's easier than bringing them here. It seems possible that disrupting all our operations incredibly thoroughly with a single scry is what Keltham was going for, here."

Sounds mentally painful.  He's glad he doesn't have to do it.  Wouldn't do it in any case, he's not having both Sevar-nonloyalists present being distracted at the same time.

"Abarco, get whoever's on the other end of your Telepathic Bond to read her comms to you, you're on relay."

Asking somebody to do that at the same time they prepare spells requires you to be pretty good, but Abarco's not really prepping those spell slots, and if his manifold collapses it just makes Abarco look stupid, which is a price Hadrian himself is willing to pay.

That sounds very unpleasantly distracting, actually, but if Sevar thinks she has enough concentration to pay attention he probably has enough attention to repeat what he's hearing. 

She's pretty sure without the artifact headband her scaffold would in fact have collapsed as soon as she started having a stupid emotional crisis, but if that didn't do it, her mail won't. And she can sense that she's intensely distracted, her thoughts racing unproductively down tangents, hiccuping over important considerations and circling back to them, not at her best - it's just, she didn't even need to be at her best, to notice this -

Elias Abarco will irritably read Sevar her mail.

Alexite Gellius Rutilus Thrune does know literally one competent project manager, an ally in good standing of his, but the first question this project manager asks will be what happened to Carissa Sevar's last project manager, a piece of information notably missing from her last message.

(Unspoken:  In political principle, Carissa could pull Crown authority to get the guy assigned to her willy-nilly; but Carissa Sevar would need to offer a hell of a favor to pry his name out of Alexite if she didn't take good care of her last project manager.)