Yukari Yakumo/Koishi Komeiji

''Disclaimer: This version of the character that the character in the RP used as the source is from a derivative work of Touhou, and thus, has only little to do with the canon version of the characters in Touhou. ''

"I’ll set you free. Free from the thought of growing older, free from everything~"

- Komeiji Koishi

Yukari Yakumo is a legendary youkai who is able to manipulate boundaries. S She is called the "gap youkai", although "gap youkai" is not the name of a species, as she is more of a one-of-a-kind type of youkai. Regardless of her power, Yukari appears to be the most well-informed being in Gensokyo of any kind, and usually achieves her goals through manipulating events rather than direct combat. Meanwhile, Koishi Komeiji is a satori youkai, and is Satori Komeiji's younger sister. An enigmatic being, she's not entirely right in the head. Due to an unfortunate event, they ended up fused together, and ended up participating in the Origin War unwillingly. Or so they thought at first.

Appearance
Despite looking like a pleasant young woman with a lovely long, blonde hair, it needs to be emphasized that she is nowhere near a woman in nature. This fact would be apparent to onlookers when they noticed the blue eye-like organ attached near her heart, the tentacle-like veins connecting it with her body, and the fact that her limbs and head are barely attached to her body, as if they could fall off at any moments. Her unnaturally sharp claws are also a sign that she is far from a normal girl, and closer to a humanoid abomination.

Freakish physical appearance aside, Koishi has dark green eyes, wears a black hat with a purple ribbon around it, that she felt quite an attachment towards it, for some unknown reasons. She wears a green shirt with diamond-like blue buttons and violet collar. The skirt is also green with a faint flowery pattern, but somewhat darker.

Personality
Koishi Komeiji

What is a personality?

Koishi's personality, to say it simply, is non-existent. Nope, non, nada. While she gave off the air of being a kooky, zany, and an airhead with a streak of apatheticness and psychotic impulses, ultimately, she completely had no personality, or at least, for this moment. Nothing resembling the concept of "mind" too. While she could still communicate well with others (if they could notice her), she acts entirely using her subconscious, her instinct.

Koishi is more similar to a mirror when her third eye is closed, her supposed "thoughts" and actions all depends on the subliminal thoughts and emotions of the others around her.

Yukari Yakumo

Yukari is known for being a very youkai-like youkai who sleeps all day and lives for the enjoyment of life. Though she rarely leaves her house, she's well-connected and is acquainted with most of the most powerful youkai as well as anyone having anything to do with the Great Hakurei Barrier or the outside world, although she rarely attacks humans. She has a tendency to toy with her opponents rather than use her full power from the start. If anyone is suited for the role of "mastermind", it's Yukari. She excels at mathematics and is experienced due to her long life.

She often has a great deal of insight and understanding about whatever happens in Gensokyo, and possesses considerable intellectual prowess, as well. Though she seems flaky and unreliable most of the time, when the safety or security of Gensokyo is at stake, she won't hesitate to get involved, even if it means using others to do the work for her. She could easily be either a villain or a heroine, depending on her whims.

Yukari usually deals with problems by manipulating others to act to resolve things for her. She seems to rarely act directly except in particularly egregious situations. In all cases, she rarely lets anyone know what her true aims or goals are, and sometimes these goals are extremely abstract. Yukari has a well-deserved reputation of being fickle, whimsical, and lying often, and thus many characters in Gensokyo dislike her. For whatever reason, Yukari takes it all in stride and does not seriously deny any of those comments. She seems to actively try to keep her more obviously-altruistic actions a secret, such as her donations to the Hakurei Shrine. She possibly cultivates this image to ensure that people continue to fear her as a youkai.

Powers & Equipment
Komeiji Koishi

Heartstring Puppetry

Koishi‘s true nature is the third eye that was attached to the body of the girl that everyone sees. And so, she has the ability to hijack an organic body as her own by attaching her tentacles into the body, or parts of the body. She could assemble new bodies from parts by sewing them together using her tentacles, but these usually ends with her forming an abomination. Though, with her currently using parts of Yukari’s body, she doesn’t have any plans to move out from her body anytime soon. Also, she has the ability to withdraw the third eye inside her current body, and by doing so, she could utilize her tentacles and subconscious manipulation more strongly.

Tentacles

Koishi’s tentacles are as sharp as razor, and they could easily pierce rocks, as she once used them to break down walls that contained her. They move quite fast. She could use these offensively and defensively. They’re very versatile, versatile enough to be able to act as replacement limbs for her, able to sew injuries and body parts if necessary, and many more options that Koishi never actually take the time to think of.

Manipulation of the Subconscious

The true form of Koishi’s power as a satori that has sealed her heart off. Her dormant ability to influence the subconscious will awaken when she was pushed enough, giving her the ability to implant unwelcome thoughts to people nearby. She did not have the person needed to back her up to make it able to actually twist any individual into depravity (unless the really weak-minded one) or to expand the influence field to cover a huge area, but she could still overload other's mind with this ability. Also, if someone was close to her for a long time when this ability is active, the implanted thoughts (which consists of either gibberish or something...else) could probably left a permanent mark on the person.

Mental Barrier

Even though Koishi’s mind-reading ability has been removed when she closed off her third eye, she still possess a powerful barrier on her mind that prevents outside force from interfering with it. This is actually caused by said closing the third eye, since it also closes of her mind completely, from herself and from other's influence.

Interconnected Hearts

All of the above abilities of hers are affected by the emotions of her oppositions. The more negative emotions she received, she become more and more uncontrollable, and her third eye become stronger and stronger. The inverse also applied. The more positive emotions are there, the more passive she’ll become. The imperfect nature of how Koishi's heart was sealed is the main cause of this ability

Yakumo Yukari

Manipulation of Boundaries between Here and There

Originally, she had the power to completely manipulate any kind of boundaries, but Koishi’s imperfect assimilation with her and her despairing had made her (and Koishi) lose that ability permanently. As boundaries of locations are one of the easiest to manipulate though, she still manage to retain this ability, much to Koishi’s happiness.

With this ability, Yukari/Koishi can connect two locations using gaps in space. Distortions in spacetime could hinder this ability, as well as several kinds of powerful magical protections. Those can be bypassed somewhat, but required quite the effort. Some protected places can only be accessed with association, meaning that Yukari/Koishi needs to use something or be in somewhere that has relations or similarity to those protected places as an entry point, examples including moon’s reflection on the water to move into the hidden side of the moon, etc.

As Koishi was still learning about the extent of this ability, her scope of usage of it is bordering on simple and mundane.

Vast Knowledge

Yukari is an ancient youkai who has more than enough time to gather knowledge on a lot of things. If she willing to share this knowledge with Koishi for her sake is another business entirely though. She also has an extensive amount of knowledge in barrier magic, which is her main type of magic.

Biography
Koishi and her sister Satori are the last of the youkai race known as satori,  as far as they know. The satori race has the ability to see into the heart of people, reading their mind. They also have the ability to possess an organic body to make it easier for them to move from one place to another.

But then, a certain “incident” in the year of 1980 happened. An experiment from Watatsuki no Toyohime, a moon princess, to forcibly close off Koishi’s third eye to unlock her true potential. She broke down the mentally unstable Koishi by staging an elaborate scenario, and it prompted the girl to fly off in rage, killing more than a hundred of bystanders in brutal ways, while the entire thing was aired to all of Japan.

When Koishi was done with her rampage, the Lunar Princess then approached her, and immediately sent her into Gensokyo with few words, to initiate the next stage of her plan. Not long before, she had appeared in front of Koishi’s sister, and she revealed herself to be another satori-youkai to her, while telling Satori that others of her kind had moved to the moon due to the ‘impurity’ of the earth, something that Toyohime desired to fix, to “erase the feeling of loneliness from being a satori”. She then elaborated her plan to turn everything else into satori, to cleanse the world from the impurities and to remove the world’s prejudice on their kind, on Toyohime’s 'children', or so she said. Satori, who grew up with her sister in loneliness, agreed wholehearted to her reasoning, and decided to help her with the “Descending Moonlight Ceremony” plan.

While Koishi's third eye opened up once more after the incident, she became more and more unhinged due to the event. In Gensokyo, both her and her sister's ability to read minds made them hated by both humans and youkais alike, and Koishi, unable to handle the pressure, closed off her third eye once again, this time willingly. This action closed off her mind and her heart alike, turning her into something resembling an empty shell, acting only based on her insticts.

One one fateful October 3rd, Koishi decided that she wanted to go fishing. Unknown to her, that impulse kickstarted the “Descending Moonlight Plan”, and residents of Gensokyo started to turn insane due to an unknown reason. Gensokyo’s caretaker Yukari Yakumo detected a huge distortion of magic on Koishi’s location, and so she decided to investigate it, thinking that Koishi was the cause to the entire event due to her power over the subconscious.

Finding Koishi there, Yukari was immediately locked into a battle with her, one that she managed to win easily, as she ended the battle decisively by decapitating Koishi. But that moment was utilized by one of Toyohime’s guards to start attacking her, revealing that Koishi was ultimately was a bait to lure Yukari so the lunarians could assasinate her more easily.

On the course of the battle, Yukari was advantageous at first despite her opponent’s Time Warp Rifle, but unknown to her; said guard had managed to get into her shikigamis before going into this battle, and turned them into living bombs which she used against Yukari.

That attack dropped Yukari’s will to battle drastically, she did not even bother to dodge her opponent's attack, or fight back. Meanwhile, her opponent used the occasion to blast her body to pieces. When her opponent left her to die, the not-quite-dead Koishi assumed it as a golden opportunity, and hijacked what’s remained of Yukari’s actually still living body. Yukari is aware of this, but the shock from the battle made her unable to do much about it. Though, Yukari retained enough willpower to try convincing Koishi to help her investigate the incident further and stop the Lunarians, but she ultimately failed to budge Koishi, and thus, her world was doomed.

The next day, she was teleported to the Hollow Asteroid somewhat unwillingly.

Arc 4: The Pathway of Origin
After arriving at the Hollow Asteroid, Koishi looked around while still wondering about what had happened, until she noticed the area covered in Mad Blood, and it sparked her curiosity to investigate it. Finding a hot spring inside, she decided to relax and chat with Yukari for a bit, though it didn't exactly anywhere for their awkward relationship. Meanwhile, Yukari was trying to figure out about how she could regain the control of her body again, as her attempts so far was being blocked by Koishi's absolute mental barrier. She noticed an opening though, and the opening became bigger and bigger as Koishi was forced to open up her mind for a bit so she could enter the Paths.

When she managed to get inside, she was confronted by a labyrinth made of rose-like growths, and she soon learned that it was set up by Koishi as a way to further protect her Self.

Quotes

 * (Catchphrase) "My hat is my friend, it helps me relax~"

Trivia

 * This is a very loose interpretation of this character. Due to the series's ambiguous nature at times, and the fact that the series was still ongoing and not fully translated, inaccuraccies will be present, whether intentional or not.
 * To clarify a bit, this is the reinterpretation of the Koishi in the KKHTA series, by using her canon self's personality (or lack thereof) as close as possible to create a what-if scenario for the series and the character itself.