There are many kinds of beings in the Anno Ruini Universe. And there are several ways to describe and classify them.
This page covers the perspective common to ‘Takuan of Koto’ timeline and to Fairy-Tale style. Thus we will talk here about gods, celestials, demons, and mere mortals.
Sentient creatures, not necessarily good or bad (same as gods or celestials); but in most cases people paint them as bad. It happens due to their selfish motivations.
Demons dwell in the Under Realm. They can break free to other Realms, but to persist there, they need a mortal body (or a sacred vessel).
When they present in bodily form (usually possessing someone), they show bestial qualities and looks. Given the kind of the looks, they can be referenced as were-wolf, were-bear, were-badger, were-dear, etc., under the umbrella of 'weredemons'.
All beings have some commonalities, but also differences. They can differ by several dimensions: where they dwell, what powers they wield, what are their motivations, and, last but not least, how they relate to immortality.
Heavenly Realm is a place where gods and celestials live. It is possible for demons to get to Heavens, but mortals require to gain immortality first. Then they became celestials.
Earthen Realm is a place for mortals. However, all other beings traverse the Earthen Realm.
Under (Bottom) Realm is a place where demons dwell. Other beings might visit the Under Realm as well, though prefer not to. No one can leave the Under Realm without assistance, it is akin to prison.
Some of the beings are very powerful, some are not.
Gods have a lot of control over magics of three Realms. They can travel between Heaven and Earthen Realms, change appearance, fly, and some other things. They, however, use their powers sparingly.
Celestials have some control over magics, mostly given to them by gods. For example, Yanwang Umma-ö is given powers to traverse to Under Realm and to banish demons.
Mortals usually don't have any powers. Some of them become sorcerers, thus getting a grip of magics of the Earthen Realm. They do it by accepting a particle of a certain god, celestial, or a demon; or by using spells and powders that are intrinsically connected with the qi.
Demons need mortal bodies to pertain in the Earthen Realm; they can shape-shift to a certain extent, and they have lots of physical power and sometimes power over elements. They can traverse between Realms.
Gods are driven by archetypes they implement. E.g., The Lucky Gods create luck (and its absence) by their own whim.
They are ancient, their age is measured in millions of years. That led to deterioration of their psyche which is succumbed under the pressure of archetypes.
They behave in archaic manner that makes them look immature at least to some extent (see Fairy Tale).
Their motivations only partially human. They might have compassion, but in general they are busy with their own affairs.
Celestials are driven by virtues or lack of them.E.g., Yanwang sees his mission in keeping demons at bay.
They are very old, their age is measured in hundreds of thousands of years. Their psyche also deteriorates, and they have to cling to something that is more persistent. Some of them choose virtues, and some are giving themselves to cravings.
Spending a lot of time with gods, their manners also archaic and sometimes immature.
Freed from mortal burdens, some of them crave to still experience mortal pleasures.
Mortals are driven by human desires.E.g., Takuan desires to be a demon hunter, and Bao-Zhu desires to live in comfort.
To desire is to be mortal. When there is death, there is fear of missing out. That fear drives some of the actions of ordinary people.
Unfulfilled desires bring suffering, which is a human condition. It drives most of their actions.
Of course, there are institutions that aim to overcome desires. Such as Monasteries.
Demons are driven by primal, animalistic passions.E.g., weredemons are always hungry, angry, and greedy.
These passions can't be satiated, only blunted. That drives their reasoning and behaviour.
Weredemons can be conceptualised as animals who ran away from Heavenly Realm. That's why they usually takes bestial form and give themselves animal names.
All beings can be killed. That is, they can be forced to halt and, in general, to exist. It is important that the killing is always forcible. The value of life is predominant to all other motivations.
Suicides, for that matter, also considered as killings, though it is not always clear who and how forces it. We'll deal with this part separately.
The beings differ by their treatment of immortality.
Mortals are mortal. When their time comes, they perish, peacefully die.
Some of them are in the quest for immortality, but others are treating their mortality as virtue.
Some manage to become immortal thus electing themselves to celestials. But most fail miserably, their life spent in fruitless pursuit.
Mortals who accept their mortality, perceive it as human virtue. To die is human. Tradition puts a lot of emphasis on it, so does the whole human society of the Calm Era.
Gods are immortal. For them, it is the only way of being they can perceive.
As they don't have a trace of mortality in their psyche, they can't relate to some of the human desires and values. That's one of the big reasons the motivations of gods sometimes are strangely different.
Celestials are ex-mortal. Once they were mortal, but now they are not.
They still cling to the memories of their own mortality albeit with different outcomes.
Some of them remember good parts — satiated desires — and crave them. Though they don't want to quit immortality.
Others remember the bad parts — suffering — and dedicate themselves to reduce it.
By doing those things ^^ they keep their connection with mortality. If a celestial lets go of these memories, he turns to a god. That never happened.
Demons are non-mortal. They have never been mortal and never will.
They are creatures, which were never born, only created.
They crave mortality and at the same time can't stand it. That drives their anger, hunger, etc., especially towards mortals.