It's sort of good to hear that Keltham's still that sort of person. It's also sort of disappointing, like on some level she didn't want to have ownership of this choice, she wanted it to be inevitable. 

She does not resist the Teleport.

They're now inside an indoors room, possibly an underground chamber judging by how one wall is rock.  There's a Mage's Sanctum enchantment, permanencied, about the whole area, and the border of a Forbiddance in front of her, with a very solid-looking and magical door ahead of that.  It looks remarkably like the Chelish safehouse/prison, really.

There's a tiefling woman here, of scarred face, dressed as a rich man's maid might be.

"Password, sweet stone sunlight.  It's a Neutral Good Forbiddance so don't forget that, it'll fry you like sausage."

"This young lady is Tarnish."

Clothes more than expensive enough to fix the scars, if she - or if Keltham - wanted that. 

"Pleasure to meet you, Tarnish."

"The pleasure is all yours, I'm sure, and it will pass swiftly.  I'm not an admirer of Cheliax's work on Keltham."  A harsh melodic voice, like this woman had been a singer before her throat took an arrow to the knee.  "I can take you to Keltham, do you wish; or bring you refreshments, or take you to your new bedroom to rest; or give you a tour of the premises, which are not large."

"...Keltham didn't express a preference?"

"Keltham is always very careful to determine others' wants and needs before expressing his own.  He'd no more just tell someone what to do than he'd smile or flirt or risk hurting somebody or get angry or have sex."

"Tarnish is not in love with Keltham, to be clear, or even fond of him, she just wants to hurt you.  I'd have warned you about that if I'd thought ahead, but I didn't think of it because of my overwhelming distaste for everything about Keltham's personal life."

Wow, this sure sounds like one functional research organization, Carissa does not say. 

"If you want to hurt me conventional methods work fine, confusing me about what Keltham wants does not. I need to talk to him, but if he's not interruptible or has no desire to see me I"ll go to my room."

She is absolutely not going to have feelings about Keltham from something someone said to her specifically to hurt her.

"I am not permitted to hurt people by conventional methods, only with my words.  Keltham is interruptible; I'll take you to him."

Character Name:  Keltham           Alignment:  True Neutral             Character Level:  2+1
Deity:  Keltham                              Homeland:  dath ilan
Class:  Wizard 2 / Alchemist (chemist) 1                                            School:  Universalist
Languages:  Baseline (native), Taldane, Osirian

STR:  9          CON:  19 (13)     DEX:  10
INT:  22 (18)   WIS:   16            CHA:  18 (14)

Magic items equipped:  Headband of Mental Prowess (+4 INT / +4 CHA), Gloves of Use Magical Device +5, Belt of Mighty Constitution (+6 CON), Tiny Sword of Glibness, Ring of Sustenance, Glasses of Arcane Sight, various others

Feats:
- Being a computer programmer who's played a lot of mathy video games
- Skill Focus: Use Magical Device

Traits:
- Dath ilani chemistry training
- Dath ilani mathematical training 
- Pragmatic activator
- Signature Spell (Prestidigitation)

Skills:
- Spellcraft: 3 ranks (+3 class skill, +6 Intelligence bonus, +2 theoretical magician, +2 magical aptitude)
- Use Magical Device: 3 ranks (+3 class skill, +3 skill focus, +2 magical aptitude, +6 int (pragmatic activator), +5 from gloves)
- Bluff: 3 ranks (+4 charisma)
- various Knowledge

That person's first action, on hearing that Carissa is on her way, will be to swap out his +4/+0/+4 headband for a +0/+0/+6 headband.  That should be maximal attainable previous-Kelthamness, and the less different he seems, the less it will hurt her, probably.  He doesn't want to hurt Carissa without a reason.

Tarnish will probably have said something cutting enough, or the Osirians warned Carissa enough of their own perspective, that Carissa will not be entirely unprepared; she should arrive warned, in a context where she'd hear the words warily rather than them hitting with all the force of reality straight out.

(He couldn't ask Ri-Dul to say anything here.  Ri-Dul made it a condition of his employment that Keltham's personal life drama would be causally screened off from him to the maximum feasible degree.  Which, valid.)

That person looks much the same, outwardly.  His face is maybe slightly thinner.

To arcane sight... he's got a headband of +6 Splendour, gloves enhancing some skill, a +6 Constitution-enhancing belt, a ring of sustenance, glasses of... probably Arcane Sight, and various other filled slots.

He is currently doing something with a flat metal plate inscribed with a complicated spellsilver pattern, spellsilver wires above that, and what looks like a scaffold or... something with a lot of moving magical parts that could not possibly be a spell, item, or anything functional at all.

He looks up at her when she enters the room.

"You look different," he states.

- she kneels. It feels less complicated that way. And if she'd do it for Abrogail and for Dispater and (without conscious decision, Dominated) for the pharaoh of Osirion, well, it feels strange to just stand there for Keltham. 

"You look different too. - I got it done in Dis. Not for you, I actually thought at the time you'd probably have mixed feelings about it, but I thought it'd help with my cult and my cult might be important."

"Let's not talk about your cult.  Presumably it's an intervention by the god of tavern rumors, which means I try to think about it as little as possible."

"Carissa, I - am not able to just resume our relationship where it left off.  If that's what kneeling to me is meant to, ask, offer."

"No, I, uh, figured that. I'm here to try to make sure the world doesn't get destroyed, and to help you find something better."

"That sounds like it should be a private conversation and probably a long one.  Can we continue this in time-dilated demiplane?"

Ooooohh, time-dilated demiplane. She wonders how long it's been for him and then cuts that line of thought off as unproductive. More than a 2x multiplier is hard to get. Probably it hasn't been more than double what it's been for her. 

"Yes, of course."

"It's new, and temporary, so don't cast from any overpowered scrolls if you've got those with you.  There'll be a 9th-circle of Sarenrae there when we arrive, finishing up the portal.  Don't talk until I've had a chance to put up a Rope Trick for privacy."   He picks up the complicated spellsilver wires and spell-diagram-like plate, sweeps it into a Bag of Holding, takes a scroll from the Bag of Holding, and a tuning fork.

He conducts her the short walk back outside the Forbiddance, then casts Plane Shift (5th-circle divine form) from scroll; slowly, carefully, but without obvious difficulty.

Carissa's feelings are alternating between declaring loudly that they're VERY COMPLICATED and apparently not being there at all. 

Why won't anyone just light her on fire until she's no longer harmed them. She bets if she went back to Cheliax they would obligingly light her on fire. 

She takes Keltham's hand for the Plane Shift, and says nothing.

Welcome to this personal temporary time-dilated demiplane!  The sky here is bright and white, like somebody took the Sun and sky and blended the colors back together.  There's grass beneath her feet, and dirt below the grass.  It's small, for a demiplane, maybe as wide across as three houses in each direction.  There's a pool of clear water that looks plenty wide enough to swim in, a house-distance away.  Walls of mist demarcate the plane's edges.

A clean desk rests next to four bookcases all of whose shelves are full of mess; there's a whiteboard, currently clean; a cabinet, one of whose drawers visibly (to arcane sight) contains a few pounds of spellsilver.  An adventurer's high-quality portable personal bedroom rig (calling it a 'tent' doesn't do it justice) stands beside.

Magic here behaves slightly oddly; if you stare around with Arcane Sight for a while, you can figure out that divination is impeded here.  A Mage's Private Sanctum overlays the whole area, but not a permanent one.

Also here is a very impressive-looking Grand High Priestess of Sarenrae, but she's busy casting the incredibly slow magic of Create Greater Demiplane.

So Sarenrae's in on it too? Or no, Keltham said he was trying not to think about Cayden's plans, so that means he doesn't consider himself to be working directly with Cayden -

She can see the outlines of the two pieces she's missing, the two pieces that'd make everything else fit together, maybe just one piece but definitely not more than two. One is what outcome Cayden Cailean and Nethys are angling for and why only they are working towards it. The other is why Cheliax hasn't attacked Osirion yet and - she's pretty sure this has the same answer - why Keltham changed course to work with the Church of Sarenrae and the Padishah Empire when she sold her soul.

He pulls out another scroll and casts again, putting up a Rope Trick, and climbs up into the space thus created, offering a hand up to Carissa if/when she follows.

She didn't even know you could do that though now that she thinks about it there's no rule you have to be on the Material to cast a Rope Trick. 

She climbs in.

"I suppose in a sense we are beginning again where we left off, inside a Rope Trick."

"There are - too many things to say - I suppose I'll just say one of them.  Why did you return my option premium and sell your soul?"