Aside from Asgard's primary races, there are also some lesser-known races. These races generally have little impact on Asgard as a whole but could still be extremely powerful or valuable. Some of these races are collectively known as the elemental spirits.
Theoretically, any element could have an elemental spirit race to represent it, like water spirits, light spirits or even illusion spirits.
In practice, though, very few elemental spirit races exist simultaneously, but new spirit races could pop up at any time, even those that had once gone extinct.
This is because elemental spirits are not born through normal means but are instead slowly formed near powerful elemental energies. Such energies, and thus the corresponding spirits, could generally be found in dangerous and inhospitable environments.
As soon as an area or treasure has reached the necessary accumulated elemental energies, spirits of that same element will start to be born and will continue to be born until the energies are exhausted, or someone takes away their source.
The spirits themselves have mostly incorporeal bodies and can't give birth to children, combined with the facts that they have a limited life span like anyone else, are only spawned for a limited time and are precious resources to Einherjar that cultivate the appropriate elements, the elemental spirits tend to die out just as fast as they spawn.
But that doesn't mean they are weak; elemental spirits have their own way of gaining power and are generally no weaker than other races when on the same level.
Therefore, sometimes, an elemental spirit race goes undiscovered long enough that they manage to get their own powerhouses to safeguard the rest.
If one of these elemental spirit powerhouses manages to reach the equivalent of a sixth-revolution Einherjar, they will undergo a profound change and, much like the beasts, will gain the ability to use a physical, humanoid body.
With this body also comes the ability to have children in the same way most races with physical bodies do, through sex. This, of course, can also lead to half-bloods in the same way as another race having a child with a sixth-revolution beast does.
But suppose two sixth-revolution elemental spirits have a child together. In that case, a whole new race is born, which, although very similar to elemental spirits in everything else, actually has a physical body and cultivates through the same path of the Einherjar as most other races do. These races are collectively known as the fairies.
Fairies have the same connection to a specific element as their parents do, and this element will generally end up as the physical element in their Einherjar path.
Unfortunately, like their parents, the fairies can bring great benefit to other races and are, therefore, often hunted down. Because of this, most fairy clans have either been turned into servants and breeding stock or are living relatively freely under a more powerful clan.
The Bönd clan, of which Lisa is one of the elders, is the latter kind and has subordinated itself to the Fenrir clan.
In return for the protection of the Fenrir clan, all the fairies of the Bönd clan have to spend their youth as spirit companions to the most promising members of the Fenrir clan.
Becoming a spirit companion means the fairy will return to their spiritual roots and enter into a soul bond with their host. Afterwards, the fairy will be able to reside in the host's soul while their physical body merges with the host.
The host receives various benefits in this form, while the fairy is safely protected in the host's soul. They can merge and unmerge at any time, allowing them to become two again in order to fight together.
The soul bond prevents either of the two from betraying the other but doesn't impose a master-slave relationship on the fairy.
After all, since the fairies will become free Bönd clan members after the third revolution and still need to live in peace with the Fenrir clan, imposing such a strict soul bond would only create unnecessary resentment.
That said, the fairies are supposed to follow their host's lead or be punished by the Bönd clan, as they are still the subordinate.
To arrange this agreement, a contest is held every five years among the Fenrir clan members aged between 15 and 20. Then, out of all the contestants, the most promising ones are assigned a fairy of the same age class.
The actual amount of Fenrir clan members getting assigned a fairy obviously depends on the number of fairies that are in the same age class at that time. After all, the Bönd clan is much smaller than the Fenrir clan. There are simply not enough fairies for everyone.
After bonding, they will become companions until the moment they have both reached the fourth revolution. In this way, both the fairy and their host will have a better chance of surviving the harsh path of an Einherjar in Asgard.
The fact that the Fenrir clan has subordinated a fairy clan is a closely guarded secret within the clan, meaning that most people don't know the Bönd clan even exists.
They usually reside in an out-of-the-way area of the Fenrir compound, close to the forest and covered by protection and concealment formations and inscriptions.
The Fenrir clan members and fairies are, therefore, also not allowed to undo their merge when outside of the compound unless the alternative is death.
They do this not only because having a known fairy clan as subordinates is equal to inviting trouble from people who desire fairies for themselves but also because of the element that this fairy clan represents—namely, the element of nature.
Nature may not sound like a particularly fearful element, but the opposite is true. Just like the elements of darkness and decay can be used by morally upstanding people, light and nature can be used by depraved individuals.
Although the nature element is second to none in healing the physical body, its ability to affect the physical body does not stop there. Basically, a powerful wielder of the element of nature can throw a physical body in complete disarray by rearranging nerves, arteries and organs.
Although the soul takes over all the cognitive thinking and consciousness after the soul core is formed, the brain is still required to send signals to the proper places.
If a wielder of the nature element manages to rearrange some nerves, you'll suddenly be taking a step when you want to take a swing with your weapon or blink when you try to wiggle your toes.
Luckily, actually rearranging nerves like that in the middle of combat is something only the most experienced and powerful nature element wielders can do.
Still, there are plenty of nasty tricks that even novice nature wielders can do to literally annoy their opponents to death.
Generally, fighting a wielder of the nature element is considered one of the most nerve-wracking experiences an Einherjar can go through, literally and figuratively.
And that does not even mention the devastating potential of the nature element to mess with the physical body outside combat.
As long as an experienced nature wielder can spend some alone time with someone, they can essentially do whatever they like to them, including giving them both pain and pleasure in such amounts that they have never felt before.
Or, even more terrifyingly, make their body addicted to something only the nature wielder can provide. In other words, nature wielders are the most effective slave trainers in Asgard. It is only lucky that they are rare.
Although both the darkness and light elements have the potential of placing marks on the soul to force someone into obeying the caster, as soon as someone removes that seal, something that anyone can do with a powerful enough soul, the marked person is free again.
Meanwhile, the nature element is much more insidious, as there is simply no mark to remove. A person enslaved through the nature element can only be truly saved by having another nature wielder undo every change made to their body and then having all the memories of their enslavement sealed or erased.
This is why nature spirits and fairies are generally feared and desired in equal measure and also why the Fenrir clan desperately wants to keep their existence a secret. Luckily, most nature spirits are kind, peaceful and freedom-loving at heart, hating the idea of slavery.
This is why the Fenrir clan dared to accept them in their home and also why the fairies accepted to be subordinated to the relatively honourable Fenrir clan.
Of course, there are always outliers. There have been incidents of fairies enslaving Fenrir clan members before, but the heavy punishment of public torture until death deters even the most vile of fairies, rare as they are.
The blood element, meanwhile, can place blood seals on the physical body, thereby stopping the sealed person from taking specific actions. But the blood element can not actually enslave in the same manner that darkness, light, and nature can.