Over 800 years old

Ambiguos, they currently present themselves as female

Item no #2
Demonic Zither
Sourpuss

Side character

Rectangular shaped body, with a very flat chest and graceful limbs - her body usually mirrors the instrument she possesses

Gloomy and cold personality, the unkempt emo-like appearance

A black and red Guzheng (chinese zither), with intricate swirling clouds like patterns on the upper side.
Her demonic form is very fluid and graceful, made of black smoke; her eyes are usually closed but when she opens them, they are shining half closed yellow orbs

Long face, with a thin nose and a permanent look of tired boredom on her face. She has half closed slanted eyes and her mouth ends are always curled downwards, in a semi sad way.

The signature black skin tight shirt, partially covered by the thin robes she's wearing, with shoulder length fingerless gloves - she wears a special type of finger armor on her pointer and middle finger, that is used when she plays the zither. Around her neck she wears a choker like necklace, with two red strings attached

Undisclosed - being a daemon, she's much lighter than a human

177 cm

Jet black

Middle back lenght straight hair, left loose

Yellow

Daemon (current)
Morphidae (former)

Pale white

Shiranui is often seen as cold and apathetic, with very little interest in what is happening around her.
She is very dedicated to her nature as a musician, playing her zither whenever she is alone - she feels underappreciated by her owner, given that she's summoned only when her abilities are needed.
Just like her friend, Shiranui holds a bit of silent grudge against Rin for snapping her chords when she was in zither form, although she conceals it way better than Hikari and she's also the first one to let it go after Rin apologizes.
Despite her extremely cold exterior, she does care about the people who left a good impression on her, as shown with the main group

Maintains a straight posture, rarely shows any reactions to various things, prefers sitting alone. Whenever she is bothered by someone while she plays her zither, she promptly stops playing, packs up and leaves. Her movements are elegant and fluid, as she always tries to keep a dignified image.

She wishes to be regarded as more than just a tool. She wants to be appreciated for her music, not her powers

She considers most people to be narrow-minded, unable to understand and appreciate her music, reason why she never likes to play for others.

She is quite cold and cynical with little patience. She has extremely low tolerance towards people bothering her while she plays the zither.

Given that she is the daemon of a zither, she's naturally skilled at playing it, although she can also play other instruments with chords

She greatly enjoys playing her zither alone, in silence.

None

Being a daemon, she does not require food to survive

Her zither

Zither

None

None

Daemon

She secretly likes turqoise

She is a quite educated person, with impecable manners and a cultured background

Not much is known about her early life as a Morphidae, other than she must have had a family at one point.
She was one of the first Morphidae to be used in the experiment - she was turned into a daemon alongside another young Morphidae, both of them being part of the early "prototypes". Because the separation process didn't exist at the time, Shiranui kept her free will, but lost all memory of her previous life as a Morphidae.
In her first years as a newly created daemon, she worked alone, before later being paired with another instrument related daemon - a flute. Unlike her, he was part of the later generation, who had their core taken away so they never interacted much. They worked together for a while, until the flute daemon was damaged beyond repair.
After that, she worked alone for a while, before being paired up with her current partner, Hikari, the umbrella daemon. After the invention of core-less daemons, she was used less and less, as her ability was not as desirable as it once was - her main purpose had been to help capture living Morphidae that were to be used to create more daemons. Once the number of daemons had increased, she was not needed anymore.
During her time as a daemon, Shiranui went from her original positive and active personality to her current cold and cynical attitude, as she's unhappy with the idea of being underappreciated and forgotten
Upon Rin's awakening, she and her partner were sent to fetch him, but since Rin had been ordered to protect his new master, he confronted the two. Shiranui had her zither strings snapped, while Hikari got off lightly with just a hole in her umbrella. Having been damaged, Shiranui was incapacitated and had to be carried away by her friend.

Once she was repaired, Shiranui decided it was best to take a more careful approach to the male demon, as he was clearly above their league.
Having no master to order them around, the two no longer tried attacking Rin and in time ended up becoming acquainted with the main group he was protecting

Cetuine

Crimson Set Daemon

Daemons usually appear as entities made of dark matter, usually smoke or fire, with glowing orbs for eyes and restraints surrounding them like transparent cages.
If they are asked to, they can take a human form that can vary, depending on the master's preferences. No matter their appearance, all daemons wear a black skin-tight turtle neck shirt, that conceals the seal drawn on the back of their necks

Out of all 24 demons, only the first 8 have personalities of their own, as their soul core was kept intact. These daemons are a little pretentious, as they must first be subdued before they can be used - most of them possess various items, as they were deemed too unstable to be used in actual weapons. Even though their original essence is pretty much intact, they do not recall their previous lives as Morphidae.
The other 16 have no core, thus they do not show any resistance in being controlled. They are often recognized by their hollow, mechanical-like behavior, acting only under the command of their owner - they are considered to be the ultimate servants, as they never question any of the orders they are given, since they do not have a mind of their own.

The Crimson set was created by Mahiru in order to wipe out the entire Morphidae race as revenge.
The very first Cursed Item was created close to when the world was still young. The rest of the items came into existence way later, after the idea of "gear" was first thought of. Many of the prototype items were pretty faulty and hard to use, but in the end, the procedure was perfected and 22 items were created, each one better than the last.
The final two items were created much later, closer to the time of the story. Rin was thought to have been the last Cursed Item to ever be created before the destruction of the experimental facilities, although there are rumors of a secret 24th item, created in secret by one of the last survivors of the project

The 8 sentient daemons have control over their actions, which in turn can give a hard time to their owners. They can complain or even refuse to lend their power.
A magic nullifier causes daemons to return to their item form, and the item itself loses any magic for a certain amount of time.

The lifespan of a daemon from a cursed gear item is unknown, usually depending on the lifespan of the object they are bound to - upon the item's destruction, the magic within it disperses and the daemon ceases to exist

The abilities of the daemons are usually closely related to the item they are bound to. Almost all daemons are capable of shape-shifting, regeneration, illusions and even minor healing.

Song of a Thousand Strings - depending on what song she plays, she can inflict a controlling effect on her target, put it to sleep. She can even shoot blades through fast motions using her zither strings.