He spends the first month after he died trying his best to avoid the demons.

He doesn't know yet why they don't seem to be doing anything with him; he knows his soul is forfeit, the theologians he spent years studying were quite clear on that point, but he'd expected that to involve some amount of being forced into unpleasant situations. 

Then again, demons presumably aren't stupid, they've convinced the world that it's possible to summon a demon safely so long as you use a good binding and don't give up your soul. They're probably trying to trick him, convince him that it's safe -- to what end? Even if they're telling the truth and he can take summons, no one will let him talk. But there are billions of them, and some of those billions are smarter than he is, and he doesn't want to underestimate them.

On the third day after his death, he finally tests whether he can make things. He can. He makes himself some food, and some tea, and then he's curious so he makes himself a copy of his apartment the day before his death, and an art project from when he was ten that his mother had accidentally thrown out, and all non-chiplocked writing from the past three days referencing his name, and three different lost libraries.

(Someone comes to complain that the libraries are blocking their view. He makes himself a car and drives until there's no one nearby to complain.)

On the thirty-forth day after his death, he finally makes himself try to take summons. He doesn't want to -- this seems like the sort of thing that would cause the demons to do something with that soul he forfeited -- but there are people summoning demons every day. There's almost no chance that anyone will let him talk, but even a slim chance of preventing anyone else from doing what he did is worth it in expectation.

He takes a summons.

The first thing he notices is that there isn't a binding. 

The second thing he notices is that the location is totally unfamiliar and multiple centuries out of date.

"Where am I?" he asks, and then "anyone who summons a demon forfeits their soul it happened to me you have to warn people -- and it's incredibly dangerous to summon a demon unbound -- who are you?"

He doesn't look like she was expecting-- but then again, daemons come in many shapes.It's not completely surprising.

He certainly doesn't talk like she was expecting.

"You're in the the Silver Savannah--" he seems disoriented, so he probably needs more direction that that "--in Ghur, the Beast Realm." 

He -- a daemon-- wants to warn people about summoning daemons? Okaaaaay. "I gave up my soul to the Chaos Gods when I came of age, I am not worried about forfeiting it. And if you were bound, you wouldn't be able to do what I want to, so that would be pointless.

I am Luehmani, Princess of what remains of my kingdom, leader of the Kleaveland Bays warband, sorceror in service of the Ruinous powers, and most importantly: looking for Slaanesh."

"I haven't heard of any of those places. Or those -- people? Gods? I'm sorry, I must be extremely lost."

Maybe she's an alien. That's actually quite plausible; people had tried, after Revelation, to have demons conjure for alien species, and the demons had come up empty, but it wasn't like demons could be trusted.

He tries making a scaled-down model of Ghur.

"You sound very lost. Ghur is a place, Slaanesh is a god. Have you heard of Azyr? Sigmar? Gorkamorka? The first is another place, the second to are other gods, if you don't know them either."

This is weird. Deeply weird. And he's probably not a daemon, which makes no sense. She's a competent sorceror! She can summon daemons! How in the Realms did she fail and what in Khorne's skull pile did she summon!

Making a scaled down model of Ghur may be tricky, considering it is essentially infinite.

When the model reaches the size he is, he stops letting it grow.

"I haven't heard of any of those. Do any of them have different names in other languages? I don't know how proper nouns interact with my understanding of your language."

He tries to make a scaled-down model of Slaanesh.

He just made a thing out of thin air-- which isn't impossible for daemons, but is still really weird.

"They do have different names in different languages. The worm-folk call 'Sigmar' 'Sah'gmar.' ...How are you understanding my language?"

Slaanesh is very magical, and sentient.

"I learned it when you summoned me." She doesn't look young enough not to know how summoning works. Perhaps this is some sort of elaborate prank, but surely no one would be foolish enough to summon an unbound demon for a prank.

He tries to make a small model of a worm-folk.

"Okay." A daemon learning a language when summoned isn't weird. He's finally not being deeply strange! ...except if he isn't a daemon, than just knowing her language would be strange. "What, exactly, are you? And no 'I'm a daemon' business. My patience is wearing thin."

The worm folk are humans! They have a very different style of dress, and on the armoured models, it appears their armour is made of worm scales and hair.

"I'm a human, or at the very least I was. A month ago by the way we count time, I died and woke up surrounded by demons. This wasn't a surprise -- I had summoned a demon, and anyone who summons a demon forfeits their soul, even if they never sell it. I also found that I had the normal powers associated with being a demon, which was surprising, since my soul was forfeit."

He pauses. "I'm sorry, I know you asked for an explanation more specific than 'I'm a demon,' but I'm not a demon, I'm a human with demon powers. I don't know how that interacts with soul forfeiture -- actually, it's possible that's what happened to me, it would explain why they were leaving me alone -- don't tell people that, they'll decide it's possible to summon demons safely. Anyways, if you want to know something more specific I can tell you."

Yep, this ritual failed badly. How, she’s not sure, but this isn't a daemon. ...Or maybe it's one thats fucking with her. Lovely.

"That's --that's not how it works. You can't be human and a daemon-- unless you are a daemon prince, which I am pretty sure you are not. Forfeiting your soul does not make you a daemon,  and it would be very convenient if it did.  Dying doesn't make you a daemon.

So, either you're lying about your past, or your...daemon-ness. So, which is it?"

"I'm not lying, but as I said I'm not a demon, I'm a human who for some reason developed demon powers. I agree that that explanation for why I have demon powers doesn't make much sense, but I don't have another hypothesis. I suppose it's possible that demons can alter memories and have done so, but they're concealing that fact quite well if so. Also, as far as I know there aren't demon princes, although admittedly I didn't talk to very many demons. There didn't seem to be much of a clearly organized hierarchy."

He tries making scale models of every demon within a thousand kilometers.

Generally, when daemons try to mess with you, they generally don't go for 'pitiful and don't know anything.' This is deeply weird, and she has no idea why this guy is so convinced she is a demon. She has no idea why he is here.

"Altering memories is a thing they can do... but the fact you describe anything they do in terms of 'organisation' is suspect. Are you sure you're not a sorceror? You sound more like a sorceror." If he is, the question of how in the Realms she summoned him is there, but 'really misinformed sorceror' at least kinda makes sense. And it explains the constant summoning of small things. What is up with that, actually. "Is there a reason for the constant summoning? I can't see any uses for dolls of worm people."

There are no demons (without an 'ae') in a thousand miles.

"...There aren't sorcerers where I'm from, for either plausible definition of 'where'. I'm making things to try to make sense of your claims, because they make no sense. I think I must be very far from home. What do you call this planet? Have you ever heard of China -- I don't have a word for it in your language, which might mean there isn't one."

He expands his search radius to four hundred thousand kilometers; if they're on Luna, it's not totally inconceivable that there aren't demons within a thousand kilometers. This doesn't look like Luna, but if this is all an elaborate prank it could be.

There are no demons.

"Your claims make some sense if you're a sorceror, and no sense if you're a daemon.

I dont know what a planet is, and I've never heard of China."

He raises his eyebrows. "A planet is the large round object that people live on," he says slowly. "There are some technical requirements, but I don't know them off the top of my head." He makes a model of Earth, scaled down to the size of a beach ball. "This is a miniature model of Earth, which is a planet, although obviously the actual Earth is much larger."

He attempts to make every camera and camera-containing device within three hundred meters. If this is an elaborate prank, someone has to be recording it.

What did he just summon. Why did he just summon. What is he. "The mortal realms aren't round like that. They’re flat."

No cameras.

"That doesn't make sense. A flat world would collapse under its own gravity. Do these 'mortal realms' have names? I don't want to try to make all of them at once, not when I don't know how many there are."

"They've never collapsed, to my knowledge.

There's 9: Azyr, Aqshy, Chamon, Ghur --where we are--, Ghyran, Hysh, Ulgu, Shyish, and Chaos."

He already has a partial model of Ghur; it certainly doesn't look round.

He tries making a model of Azyr.

It's a cityscape, with high towers made of marble and gold and other valuable materials.

Is it flat?

It's flat.

That's absurd.

"Apparently you're correct, which is absolutely ridiculous." Although, now that he thinks about it, someone had claimed that Hell was on a flat plane of gold, so perhaps this was not unprecedented. "Can you tell me more about your world? Demons are apparently known here, but are angels and fairies?"

Luehmani remains confused about why this guy is just summoning a pile of stuff.

"Why wouldn't the realms be flat?

I don't know of anything you could accurately call angels or fairies. Some people call the Stormcast Eternals 'angels,' but they are wrong. Very wrong. Fewer still call sprites or elves fairies, but they are also wrong."

"It's been almost two decades since I've taken a physics course, but I can try to explain it -- do you know what -- I don't have a word for it in your language, so you probably don't have the concept yet. We have a concept called 'gravity.' It's what makes objects fall when you drop them, but it's actually a force between any objects, pulling them together. The way it pulls on planets makes them spherical rather than flat.

Where I'm from, you could summon an angel or a fairy with the same process you would use to summon a demon. Is demon-summoning common knowledge here? If it were, I would expect you to have heard of angels and fairies by know, although perhaps you consistently gag your demons."

He tries making models of a Stormcast Eternal, a sprite, and an elf.