Spirit creatures in Aelsif

Aelsif's a weird setting. Spirits are weird even for it, and they're very common. I am absolutely looking for feedback on this concept, because I know it's weird and I want it to be interesting, rather than nonsensical.

Imagine a big, snarled up ball of cords floating in the air. Now imagine the cords are able to move on their own, and hang loose from the ball. Now, imagine it expands out as much as it can, and you can see the core structure is actually a single braided ring of fibers, with long strands protruding from it. This moving ball of cords is a sprite, the actual creature at the core of a spirit.

Now, imagine a collection of cords around another central ring, next to the sprite. This collection of cords reaches up, left and right, and down where it split up to form a wireframe model of a T-posed human body, complete with features from digits to genitals and even hair (head only), though the hair is represented by a very small number of strands since this IS a wireframe. Parts more important to their identity are exaggerated, but parts that aren't important are understated, IE they have big heads and small feet. This is the spirit's body. The sprite docks into that ring in the middle of the torso, and extends its cords into each body part, wearing it like power armour. Let's imagine this wireframe is about 30cm tall and feminine, completely unendowed and with short limbs (especially legs), with straight, simply parted hair and bangs that reach the top of her eyes. From her back, the wireframe reaches out in four simple, off-diamond shaped wings, two large and two small beneath it.

Now, let's colour that wireframe in with a grand illusion. Grand illusions are illusions with a hefty component of real energy that makes them everything short of real, and they're the basis of a spirit as we see them. The grand illusion draws them a form around their wireframe. It has no texture to it, it's just flat colours and gradients, if you look close you'll never see the tiny lines of human skin because they aren't there, and there's no hair either except for on her head. Looking up to her head, we see her hair is solid pieces. Her head is big, her eyes are huge, and while it's visibly obvious she's not real she is a little girl with butterfly wings. Now, picture an appropriately diminutive backless dress for her to wear, so we can move on.

Let's start with why the dress is backless, because it's not just a fashion choice. Let's have her sit criss-cross in a stable position, leaning forward, and ruin that cuteness she's got going for her by showing again what she really is. Let's have her exit her body's back, right through the open back of her dress. For a moment, there's a visible hole in her body. That quickly closes back up, and her body's just sitting there, lifeless, with her floating separate from it. (That hole is actually why a backless dress. She could exit through the collar of another dress, but that's more effort and you couldn't see the hole she left.)

Now, imagine her sprite's cords reach out to form arms, legs and a head, like they did inside her body, but without the body a lot of detail is missing. It's not a wireframe, it's more like rigging. Now, let's generate the fairy child using this simple rigging. Unfortunately, a lot of detail is lost and some changes were made with this crude base. The exaggeration of important features and understatement of unimportant ones is so strong she's gotten a bit shorter and her head's as big as her torso now. Her wings lack complex patterns, her hands and feet lack digits, she doesn't have hair she just has a head shaped like there's hair on it, and in fact a lot of details are missing because while she may initially look to still be wearing an identical backless dress, that's actually part of her and in fact if you were to check her skirt is a solid piece with a bottom to it and her legs just come out of it. She legitimately does not have knees right now, which is okay because she doesn't have elbows either, her limbs are loose noodly appendages. (More than they were, anyway.)

This is called a "ghost", and it's a temporary body used when a spirit needs to operate outside their body. For example, if somebody was to hack her in two while she's in her body, her body would disintegrate to ash and she'd eject. Her sprite would fly off at supersonic speed to somewhere far, far away. When she landed, she'd make a ghost to make due until she could make a new, proper body. For an example devoid of infanticide, if she just wants to run over to a friends house she can exit her body and fly over there as a sprite, making a new body when she arrives at his place, but since she lacks features it's not as good as bringing her body. I mean, she went to a boy's house, and he's going to be awfully disappointed. He got paper out and she can't draw without fingers.

But, the ghost has features the body doesn't. I mentioned she formed a dress at will, but what if she wanted more than that? Let's give her a present while she's in her body. It's a tiny fountain pen. Let her play with it for a while, get used to having it on-hand. Well, now that she's used to it being on-hand, she can form an identical fountain pen in ghost form, and if her little friend has an inkwell she can still draw despite not having fingers. Or, perhaps, she'd rather not be a person right now. She can simplify down to a little glowing orb with wings if she needs to, and go flying around like that. She'll even gain better flight speed and some unique support abilities (depending on her kind of fairy), but she's losing any equipment she could generate before, as well as, you know, arms and legs.

But, what if somebody takes a sword and cuts her ghost in half? Well, her ghost will disintegrate and she'll go flying off into the sunset, but having lost her ghost she's lost the energy to produce a ghost. It'll be a day or so before she can make a new one. That's at least faster than she could make a whole new body, and there's no serious cost aside from time, but the yarn ball will be a little girl again soon enough.

Now, the unthinkable. What happens if her sprite is destroyed? Well, if it's destroyed while in her body she'll cannibalise her body to revive it and eject at top speed, leaving a pile of ash where her body was. So she legitimately cannot be killed while in her body, unless you were to obliterate her sprite and body at the same time. On the other hand, if her sprite is destroyed while in ghost form, she'll disintegrate into ash and there'll be nothing left of her. The same goes if she's destroyed while she's just a sprite, but she's so little and so fast when she's a sprite (just imagine trying to hit a supersonic golf ball) it's unlikely anybody could ever tag her until she slows down. It's entirely possible to kill a spirit permanently, if you recognise the sprite as the actual creature and target it specifically.

Okay, less unthinkable but still not exactly on the up and up. What if she leaves her body behind and another fairy child finds it there? Can their sprite dock into her body and steal it? Well, yes. Yes, they could. And that's why they keep their bodies close at hand or at least leave them in the custody of somebody they trust or where nobody else will find them. This is especially important, because as limited as it is, their body is most of their power. Their body is dramatically stronger and more durable than a ghost, still not as strong and durable as a real creature, it can effectively use equipment that isn't part of them, and is even able of reproduction. (Well, normally. Obviously she's way too young, that subroutine isn't enabled yet.)

Okay, so what if she loses her body and her ghost, but her sprite survives? Well, in the mean time she's stuck as a little yarn ball. She can generate a 2d image to communicate with people, but she can't interact with anything physically her sprite can't move in its very limited state, and that means she can't make any sounds. Her image will have to improvise. Pantomimes? A text bubble? Something to tell you whatever she needs to say. Probably something about removing an obstruction so she can get back in her body.

Of course, spirits aren't always children and fairies are only one common type of spirit. Perhaps the spirit you encounter will be a big one-eyed brute with a kanabo, or a busty broad with bat wings whose ghost can look like the chibi version of anybody you'd like, a master martial artist with a big nose whose ghost shapeshifts into a bird-man, or a catgirl whose ghost can become a cat. Or a fox spirit whose ghost can form eight extra tails and immense arcane power as a kind of temporary transformation power-up. Or a flying squid that can become a spool of 5m long tentacles with seven eyes, three mouths and a scream that rends the minds of those who hear it. You know, basic stuff. And even that little fairy girl, she'll grow up eventually. (To a whopping 50cm, but still.)

TL;DR: Spirits are small creatures resembling a snarl of wire that projects a grand illusion to interface with normal creatures, can generate and project multiple forms, and has a preferred form it can make a more physical version of and it needs to be in for a wide variety of functions. They're easy to defeat in combat but hard to actually kill, the pieces of them generated turn to ash (makes a good seasoning) when destroyed, and they're fully sentient, sapient and reasoning and are in fact able to be playable characters with unique enough advantages to compensate for their ineptitude in combat.

And if that doesn't make physical sense, if you can't visualise how it works, we've failed.