Preternatural is the broad term for someone who is not human. They could be Angels, Born Angels, several types of Demons, Shyfters (no, that's not a typo), Vamps, etc. Preternatural(s) is often shortened to Preter(s). Some simply call them non-human, and others purposefully or ignorantly label them demons.

Note: I will be making an exhuastive list of them in a blog post that will be featured here.

If you like reading in Chronological Order, I suggest picking up A Born Angel first, but you could also read The Stained Angel or if you want the spice, start with Discord's Nightmare. You can find all the books over in the shop with more info over here.

Demons are just a term for the lower class of Preternatural that can either shyft or have only one kinetic or elemental ability. I.E. a were-wolf or were-bear, a Fire Demon, Blood Demon, Bovinus/Bull demon, etc. Not to be confused with a Chimera, who has at least two but no more than four shyfted forms or an Animorphis is a shyfter with five forms or more. I will be putting out a chart of Preternaturals in a blog for reference. When I publish that, it will be linked here: (Not yet posted)

Simply, A Soulmate, or Ki'Taoahmma in Demoki, is literally the soul's mate or, you could say, Fated Mate. The more complex answer is A Soulmate is the Maker ordained person, or people, who will meet your needs and wants. They are exactly who your soul needs. When a couple, or throuple in rare instances, come together they enhance each other's powers, and heal broken bonds, bodies, and even minds.

Note: only Angels and Born Angels have soulmates in this sense, but they can be bound to someone who is not an Angel or Born Angel. 

A Triumvirate is a group of three Angels sharing at least one aspect. Most Angels have three Triumvirates, one for each of their aspects. If all three Angels of a Triumvirate are in one place, harmonious, and acting together, their powers will be heightened and they will be more effective. Coincidentally, if one Angel of a Triumvirate is Corrupted and has broken their connection the remaining Angels may seek out a new Angel to close that triangle so they will not be weakened. 

For Example: one such infamous Triumvirate is the Deadly Sirens. Discord, Havoc, and Chaos who share aspects of Music and Death. 

In short:
I come from a Christian background (though I am no longer "practicing") and believe the world was Created by God (and still do). This translated to their Universe.

Long Version:
The Maker is their omnipotent, omnicient diety, and the "Created Angels" are the Angels that were created before the world and before Mortals ever existed. He still watches over the world, even though He is not responsible for all that happens as many of the evils that take place were beings malevolently acting against his orders. He sends his emissaries sometimes Angels, sometimes other preternaturals or humans to go after these people to redeem them or to kill them. He still talks directly to some Angels and even some lesser preters as well. He also set up the different Pantheons of Angels to take care of the humans in different regions of the world.

This is quite difficult to outline in one paragraph, but I'm gonna try my best to do so consistently and concisely. 

There is a Governing body known as The Council (usually "Of Something," each new Council chooses a different word that encompasses their term, which is usually a lifetime or 2-3 thousand years). This Council rules over ALL preternaturals, and to further aid them, they created the law enforcement agency known all over the world as the Preternatural and Mythical Creatures Agency, which was established in Athens, Greece in the 1940's. This Agency has several offices, or bureauxes, all over the world and several smaller stations or sometimes just a unit within a police department that handles the preters in their area, depending on how many preters are in the area, as taken by census. 

The simple answer is it varies from Country to Country and even State to State within said Country.

For Example:
Some cultures have known about preters and have included them in their teachings and lore since their inception. On the other hand, there are places like the United States, that thought them myth, folklore, and hoax even after the aforementioned Agency (see How is the governing of Preternaturals Structured) was founded in the 1940s. It took until 1969 for it to be accepted truth in the US and a branch was opened in Los Angeles in 1970. It also became their headquarters as Lucifer, then head of the Agency, moved there.

    In the Kalista Chronicles (approximately the first ten books), the knowledge of preters is growing and the history books are being rewritten to include preters and all that they did. By the time of The Stained Angel (approximately 20 years after the happenings of A Broken Redeemer), Preters are accepted and are common knowledge worldwide, except for pocket communities that are isolated from the rest of the world. BUT There is also a group of humans who are against Preternaturals and think they should be pushed back into the dark until they are merely Hoax, Myth, and Folklore again. 

This is a tough one to answer.

The Simple answer:
They just come to me.

The Harder answer:
I draw inspiration from all over. Mythology, games, books, art, and yes, even real people, though I try not to make a character 100% like any one person. For Example Odin, Forseti, and Max all have aspects of my favorite person... I won't name him here. He knows who he is.