He needs to summon another demon, and he needs to do it fast. He whips out the Black Book, flips desperately through its pages, and arranges the offerings around the iron circle set into the floor of his basement. A phonebook, a pile of dust, a miniature casket, a oh my god he got in screw it he'll do it without the rest!
He forces an immense amount of energy through his body into the summoning. The dust whirls into the air. He screams as his skin crackles and snaps with static. "I summon thee! I summon thee! I summon thee, K-Kh-"
It is possibly the most regrettable sneeze in Mortimer Halliwell's life.
There is a plume of red flame, and there is someone in his circle.
"This is extremely irritating," she observes calmly. "I am extremely irritated."
Mortimer controls his natural instinct to stutter and flee. He is the summoner! He is in control! That is definitely not the three-horned demon Khadarosh, but he is still in control!
"I command you to go upstairs and slay the man who has entered my home!" This is accompanied by what Mortimer endearingly believes to be a spear-thrust of implacable will.
"I am disinclined to fulfill your request," says definitely not the three-horned demon Khadarosh.
Mortimer would like to phone a friend.
No friends are available, but there are a few loud crashing sounds coming from upstairs. Accompanied by hearty laughter, presumably from the blonde maniac. He twitches. "Listen, I think we got off on the wrong foot. Could you... please destroy the man upstairs? He's making an awful mess. And I think he wants to kill me."
"It's true, he is behaving untidily," she says. "But he has done fewer annoying things to me than you have. Perhaps I will wait for him to arrive, and find out exactly what he is trying to do."
"I wasn't!" whines Mortimer. "I summoned her! She's a demon!"
"You're just making things worse for yourself, Morty."
"I am not a demon," says the woman in the very nice armchair in the circle. "He did summon me. I am annoyed about it."
"She's a demon! A horribly powerful demon! She barely noticed the spear-thrust of my indomitable will!"
Ari shudders. "I just ate, Morty."
The question of whether or not she's human is definitely debatable, but she isn't very interested in it, so she doesn't bring that up.
There may be some kind of death goddess in Mortimer Halliwell's basement. Ari has a new priority in this situation, and its name is damage control.
Ari makes a brutally efficient gesture with his feet, and Mortimer is swallowed up to his waist in the bedrock. He opens his mouth to complain, but it's shut and covered by a flying strip of clay, which rapidly bakes itself solid.
He takes a folding chair off the wall and sits opposite the administrator, his face neutral. "What do you mean by... "admistrator"? Is this related to the fact that you aren't meaningfully restrained by this circle?"
"I am the administrator of my domain. I prefer to let its inhabitants deal with their own problems as much as possible, but I arranged the rules by which people and objects are distributed into it, and other things such as its basic physical structure and the very convenient rule that inhibits the accumulation of dust on surfaces. The incompleteness of this world's afterlife annoys me, and I believe I would like to do something about it. I dislike impermanence."
"So, you have as much power here as you do in your own domain? And our afterlife is "incomplete" how? For that matter: we have an afterlife?"
"You have an afterlife, but it collects only a subset of the aware life of this world, and it seems even those may be permanently destroyed under the right conditions. I am not pleased about that. I lack the kind of direct control here that I would have in my own domain, but I am still able to do some things, such as instantiate physical objects." She gestures at the chair she is sitting in.
"So you want to make your domain the place where good little sidhe go when they die?" he clarifies.
"If sidhe are a form of aware life that does not currently go anywhere when they die, then yes."
"Yeah, I think that's what you're talking about. Can you tell by looking where, say, I would go? Or Mortimer, over there in the sinkhole? Because I'd like to be sure of what you're proposing."
Ari claps his hands together. He's kind of excited! It isn't every day you go after a minor-league demon summoner and end up chatting with a death goddess in his basement. "Good, good. I'd like to perform another test; could you step out of the circle? It's become pretty clear that it doesn't matter whether you're in or out."
"Was that very informative?"
"No, I just wanted to use the circle. Though it was good to know." He reaches into his backpack and pulls out a bag of sliced bread and a tiny plastic bear of fake honey. He applies the honey liberally to the bread, pushes the chair to the edge of the circle, and places the bread in front of it. Then he cups his hands around his mouth and whispers a name three times, too low for Morty to hear but possibly audible to the administrator.
"I want to give you this delicious honeyed bread," explains Ari.
"Why?! Why do you want to give me the delicious bread? Is it poison? IS IT?!" screams the faerie in a shrill voice.
"No. It is delicious. Eat the bread."
The creature's wings hum in the air as it weighs its options. Then it dives towards the delicious bread and tears into it like a starving vulture into a week-old gazelle carcass. It is a grisly sight.
Ari turns to the administrator. "Could you tell me if this sprite will go to an afterlife when it dies?" Before the sprite can begin screaming, he repeats, "The bread is not poisoned. It is delicious. Delicious things are not poison things." The fairy acknowledges his logic with a birdlike nod and returns to its gruesome meal.
"This creature belongs to one of the categories for which no afterlife currently exists."