"I don't know very much about how that would be done but we can definitely ask."

Any reason they shouldn't go set that in motion literally right now?

To the High Priestess's office it is!

Of course.  It will be her pleasure.

(What exactly is to be her pleasure, Sevar?  There's no guarantee that the next devil summoned will accept Sevar's contract now, and faking a compact with Keltham is probably sufficient for Sevar to lose her Law.)

Luckily, they have to do the part with the devil outside the Forbiddance since you can't summon an outsider into one; that means there's an ironclad excuse for Keltham not to be present for it.  Carissa is hoping that the reason for the instruction that she is not to sell her soul this day is in fact that she's meant to do this, as part of seducing Keltham to Evil. If not, though, and they still won't buy her soul, she wants to draw up a very real contract giving Keltham a very real option on her soul, which avoids specifying that it is presently owned by Hell, which she and he will sign. And then claim that it worked but the option makes it much less valuable so she doesn't get the perks, to explain the lack of Permanent Arcane Sight.

Unless to the High Priestess's awareness this is a stupid plan, in which case she can just tell them that options like that don't exist to her knowledge.

...no, that's impressively clever, Chosen of Asmodeus.  They shall need to consult a devil whether or not her soul is saleable this day, to make sure the language of this new contract is enforceable and valid, but the High Priestess expects it is doable.

Is it your will that this be done at once?

The only cause to delay Carissa can see is selfish, that she can't easily be made to do this and it's not clearly in her interests - sort of the dilemma of whether it was pathetic or noble of her to sign Contessa Lrilatha's contract without enough time to read it, given that it was what Asmodeus wanted but also that it's not Asmodeus's job to make doing what He wants non-catastrophic for her. But on this Asmodeus has specific instructions, that she is to serve Him well and come to Him in Hell without thought of other choices and be treasured, and okay maybe she's not living up to that instruction just yet since she clearly had that thought process but she thinks she's being told that it is Asmodean, in this case, to serve without thought for her own interests. (Does that sound right?)

Anyway, yes, it should be done at once.

Jacint informs Keltham that this process must needs be carried out beyond the Forbiddance, since devils may not be summoned here; and it seems obviously unwise that Keltham step outside the Forbiddance without great need.

Aside from that, it can be done right now.  Though Carissa will probably come back bearing a compact regarding the option on her, for Keltham to sign, which must needs be signed before the devil signs with her, for obvious reasons.

Somebody's going to have to explain the language of the contract to Keltham, pretty darned carefully, especially if this is being done in a way where he's not getting Contessa Lrilatha's assurance about the compact being designed without intent to cause unforeseen consequences.  Please factor that delay into account.

Message to Jacint:  And furthermore Keltham needs Jacint's personal assurance on a level falling barely short of Abaddon-oath, that Keltham not being there is absolutely not going to allow any pathway through time however improbable where, somehow, it looks like Carissa sold her soul, but actually she didn't, and also after that nobody ran the additional check on whether she was a hidden cleric, or the check happened to a disguised double of Carissa or something.

Split-second deputy's decision:  This seems like a safe assurance to give Keltham, it should not hurt Cheliax to run that additional check on Carissa.

Actually if Carissa tried to forbid that, Jacint herself would start to feel nervous at that point.

Return Message:  I do so promise.

Carissa will also want to give the contract a really close read! Obviously a devil who pulled tricky shit would not have excellent reviews and be on a recommended list, but still, the stakes are higher here and they should be incredibly careful.

Jacint will head over to collect rather a lot of Security and scrying protections, and then she and Carissa will step outside the Forbiddance to do the necessary.

Keltham will find something else to do with himself, he supposes.

(The first Pending Thing not requiring the full harem, that came to mind, was resuming flirting with Meritxell.  Would that be inappropriate?  That's possibly inappropriate, right?  Maybe he should just continue trying to read things.)

Asmodia heads over to the real main temple, the one Keltham can't visit and can't know exists because it contains the actual torture chambers.

The door opens to a Security's private bedroom; the Security on duty here is apparently asleep in bed, startling awake at someone opening the door. When he identifies Asmodia he presses a panel that opens a nonmagically concealed door behind his bed.

Asmodia heads through, drawing what confidence she can about her.  It's her first time visiting this part of the installation, so she's looking around to see what's here.

Also, do people here seem at all impressed with meeting a Project Lawful whatever-she-is?

They haven't had a lot of time and haven't spent much of it on the decor in here, where Keltham won't see it; the temple itself is done well enough to honor Asmodeus, in black stone that must have been laid by magic because stoneworkers can't work that fast, but the rest just looks like a repurposed fortress, thick undecorated stone walls and floors with periodic magic torches, slightly overcrowded with support staff not cleared to meet Keltham.

The staff here stares less than at the palace, either because they're more professional or have heard less ridiculous things about Project Lawful girls. They do get out of her way.

Okay.  People getting out of her way is... well it's kind of a lot actually.  She needs to not blow this.

Message to whoever looks like the best prospect for directing her onward:  I need to speak to whoever is maintaining comms with Egorian.  Privately.

Office next to the temple.

The office contains a fourth-circle priest of Asmodeus and a Mage's Private Sanctum enchantment so walking into his office is like walking into a wall of fog, after which she can't hear out at all.

Message anyways, just to be sure:

I need to send a message to Gorthoklek and receive a return message and verifiable authorization from him, with the literal absolute minimum of people who are not myself and Gorthoklek knowing that a message was exchanged between us, and literally nobody except the two of us knowing the contents of that exchange.  Advise me on protocols.

This priest has been warned that Project Lawful is ridiculous, no, more ridiculous than that, no, you're not prepared for how ridiculous, but this is somewhat more ridiculous than he expected. This girl's file doesn't even suggest that she's at all one of the interesting ones!

"....ah," he says. "Hmmm. On what timescale do you need to send your message."

She guesses that if he's answering out loud, given that question, this room is actually believed secured.

"Give me timescales and their privacy costs - how much privacy would I lose if I wanted this done as quickly as possible?"

"If you wanted this done as quickly as possible I would have you impersonate me and request a Teleport to, uh, the front in Nidal, where you could get in Telepathy range of him with your request; the primary costs there are not in privacy but in your safety. If we have more time, I'd make a secret request for his whereabouts and notify you once he's neither at the front, where you'd be in danger, nor in the palace, where an attempt at impersonation would be noticed instantly, and have someone convey you-as-me there."

"I see.  That sounds like it requires a longer and more visible absence of myself from Project Lawful than I'd hoped for."

"Possibilities and costs around sealed written message to him marked his-eyes-only, with only your name on it in capacity as comms officer, minimum awareness of that event, sealed reply addressed to yourself and returned to me?"

"I consider it very unlikely that someone loyal to us would read that; there exists the possibility it would be intercepted; the person who Teleported and delivered the message would be aware of a message from me to the target but probably not expect your involvement."