Demons

"I can do what you ask but there will be a price...Your soul?...oh no no no little mortal, that is worthless to me...I want the thing you love the most and is more precious to you than your soul..."

Reponse from a unknown demon to a summoning

In the many worlds of the omniverse, demons are supernatural entities that call another realm/plane/dimension home. Easthalen is no exception. To be classed as a demon, in Easthalen at least, the supernatural creature needs to meet several criteria:

1. Not call the prime material plane "home"
2. Can be summoned to the prime material plane by another creature
3. Not bound, by any means, to any of the major deities.

Some scholars argue that there should also be a fourth definition, that the creature should have some kind of evilness about them, but this is a debate, like many other academic ones, that has been going on for centuries. For that fact is, demons are not inherently evil. They instead reflect the personality of the one who summoned them. Those who are "good" will, assuming the summons works, will get a creature visiting them that could, under certain definations, be classed as "good."

Unfortunately, the vast majority of rituals (that work) to summon a demon would involve activities that the vast majority of good-aligned people would baulk at unless under the direst of circumstances.

It also doesn't help that, when translated into the common language used in the summoning rituals, that the demonic names, both the so-called true names and the use or summoning name, tend to sound...well..evil.
Some example names can be found below , in the format True Name (Use Name):

• Bemocoguu (Blightloose the Torturer)
• By'shcc (Breaksharp Vexscum )
• Mazba'yi-oo'ma (Scrapecrush the Blighted)
• Uuoa'thlay-dach (Mouldersuck the Trickster)
• Au'ou-e-de (Scumblood Warpfat the Deformed)
• Uunyroy-aaow (Lipgut the Depraved)

Combine the other reasons, the reflection of the summoner, the often macabre rituals need to summon them and the fact that their names sound like they do and you can see why practically all demons that are considered "native" (in the sense that they are commonly summoned there) to Easthalen are the way they are.
The flip side to this also works: Those who successfully summon a demon with a ritual that is considered to be "good", with pure or noble intentions and the demon happens to have a "nice" name, will summon forth a creature that might in some cultures be considered angelic. But this does not mean they will get what they want and many tales have been told of an unfortunate soul summoning what they believed to be something good and pure, only to have been tricked. A popular saying, amongst those who know about the fluidic nature of the demons/angels, is you often get what you asked for, not what you wanted.

The demons (and the so-called angels) appearance, goals and powers are as varied as the mortal that summoned them. But again, this is modified by the expectations and knowledge of the mortal that brought them forth. The more a creature is summoned in one particular form, the more likely it will be summoned that way again as its appearance will reinforce the image mortals have that is associated with its name.
This can sometimes have a peculiar effect on those demons that have multiple names, in that one name causes them to manifest as a demonic creature in one form, but angelic when another name is used. There is a popular story that two different summoners had summoned the same creature, one in its classic demon form, whilst the other had summoned the same demon by using one of its other names, in its angelic form. Both, without realising they had summoned the same entity, commanded it to destroy the creature the other summoner had brought forth. From all accounts, this was the easiest summoning the demon had ever had and walked away with not one, but two things it desired.