Please be aware: Anything labeled :MnRn: is subject to having spoilers. Read at your own risk.
It happened a very long time ago. Even the Shadow Acolytes don't remember. Since they come into existence only to resummon Ciar when the time is right, time has become meaningless to them.
At the time, there was a cult of darkness in Japan. They always sought to cause chaos wherever they went. For the most part, they were fairly unsuccessful. There were thirteen of them in all.
They had a fairly large collection of literature and scrolls pertaining to the dark arts, some of which was brought in by travelers from faraway lands who sought people who shared their interests. Most of it either didn't do what it was supposed to, or failed to do much at all.
However, one person had found his way into this collection while the leader was away, so hungry for power that he would betray his own people. He had found a spell which was unlabeled. Their master forbade them to use unlabeled magic unless it could be used in a controlled environment. Although they wanted to create chaos, they did not want to destroy themselves in doing so. He began incanting. A surge of darkness flowed within the room.
A fellow cultist had seen him enter the library on his own. He alerted the master, who alerted the rest of the cult. If he was using unknown magic, force might be necessary.
By time they returned to detain the traitor, it was too late. He had become...different. His eyes turned black. They practically absorbed light. His skin began to turn black as well. Dark mist began to emanate from him. He gained beastly strength and ungodly power. They tried to stop him. They tried to end it. They could not do so.
The first two people the beast could grab on to... Their souls became eternally bound to it. Eva Nagakuro was first. She had been the morale leader of this cult. Whatever they set out to do, Eva would be the one to make sure everything would happen as it should.
Takeshi Hoshiyama was the second. He was the antagonist of the group. They thought for sure he would defect, and that it was him who had snuck into the library. He seemed to hold nothing but contempt toward everyone, but desired not to be a traitor.
Whomever the beast could grab onto afterward was simply killed. It seemed hopeless. However, someone had a plan in case of such an emergency. A man and a woman, whose birth names have been since forgotten. They had something that the others didn't. They had love. They also had a book, one that shone brilliantly. It was kept secret from the others. It was secret no longer.
They grabbed the book and began to incant. The beast was successfully held in a circle of light. Together with the remaining survivors, they were able to seal away the beast. However, they did not know how long this effect would last. Furthermore, they did not realize that the souls it had taken would rise again, and again every time the beast had the strength to break free.
Four remained. The two lovers, a Gaelic man, and an Indian woman. It was the Gaelic man who would name the creature after its pure darkness, in his own tongue; "Ciar". The lovers would take the name Akari, and forever watch over this creature. The Indian woman was able to determine that all four of them were cursed, as would be their entire lineage, until the darkness could be permanently defeated. As a result of this curse, they could not defeat it themselves.
They all went their separate ways after that. (Of course, the two Akari left together.) Neither person knew what was the fate of the others.
Akari, being the ones who took responsibility over Ciar, would be the only family able to stop it...but not directly. Every natal member of the Akari family has a perfect soulmate; one person who they are always in tune with. This person is able to share the most into the family's magical abilities without being bound to them. This person and this person alone is able to defeat Ciar. However, once they are bound by marriage to that energy, they also share in the curse, and become unable to do so anymore.
Its defeat, however, is not quite a victory...
Once defeated by the last born Akari's soulmate (hereafter known as the Hero), Ciar launches a final attack. It incapacitates the Hero for a while, but seems to do little else. Shortly after the next full moon, its affects begin to become apparent. Aggressive behaviour, increased seclusion...
However, by the new moon (more or less), it takes over. Ciar's soul begins to infect and take over the Hero's body. The Acolytes are reawakened, and are assigned to take the Hero and bring them back to the lair where the whole thing started. There, on the next full moon, the Acolytes perform a ritual which will allow Ciar to come forth and live once again.
Ciar is at its weakest at this time, but its permanent defeat is not so obvious. If the Hero is killed, Ciar will simply jump into the killer's body, or failing that, any other suitable body it can find. The Hero can also be sealed, but that only helps to ensure that Ciar will rise again some day.
The last born Akari must find a way to reach into the Hero's soul, make them strong, and bring them out once again. Once the Hero has regained control of themselves, a kiss of true love will serve to dispel Ciar once and for all.
Eva Nagakuro, the first Acolyte
Eva Nakaguro has short, red hair, and mesmerizing green eyes, such eyes that would cause any man to melt at her gaze. She is physically frozen at 24 years old, as part of the curse wrought upon her by Ciar. If she is speaking to a group, she usually wears a look of strength and determination. However, if she is standing in the background or having a one-on-one conversation, her look will become very mischievous, with a very slight, lustful smirk on her lips.
Eva seemed to appear, as if out of the shadows, shortly after the cult had formed. Any attempts to trace where she was from -- albeit this was a long time ago, so perhaps their information was just limited -- would have no result. She seemed very much interested in the dark arts. And for that matter, interested in the Master. She got in without much problem.
She always seemed to know just what to do to motivate the group. As a result, she was quickly posted as a sort of morale officer, at the Master's side. However, although she was attached to the Master, that didn't stop her from having one on one..."sessions" with most of the male members as a private motivation to get done what needed to be done. And despite these acts, nobody knew anyone was getting this same kind of treatment. Those who didn't partake were still mesmerized by her charisma, and would follow her to the ends of the Earth.
All but Takeshi. He thought her entire act was simply gratuitous, and wanted no part of it. Why he followed the group at all, nobody knew. Why he was still in it, how he was still in it, nobody knew. Why Ciar picked Eva and Takeshi to be its Acolytes, nobody knew. They never got along. Maybe it was random. Maybe it knew what it was doing. Clearly, it didn't expect Takeshi to defect and spill the beans at some point... Or perhaps it did...
Takeshi Hoshiyama, the second Acolyte
Suffice it to say, he was the troublemaker of the group. Although he was very much interested in the dark arts, he was kind of scared of it at the same time, and as such, tended to antagonize the group.
He has jet black hair, and chimera red/blue (left/right) eyes. He is physically frozen at 18 years old, as part of the curse wrought upon him by Ciar. He has an angry, yet youthful look in his eyes, and is rarely seen with a smile. In front, his hair is accented upward, then comes down to about his eyes. In back, it goes about midway down his back. Both sides, it's parted right in the middle.
There is a scar present on his face, running from the far corner of his right eye to the left side of his jawbone. On his back can be seen several scars as well, most of which are covered by his hair. He is fairly toned...after all, he's drawn in anime style.
It turns out that Takeshi was selected specifically to put an end to Ciar. While Ciar was taking over its summoner's body (hereafter named The Summoner), it used his knowledge to select Eva as the first Acolyte. However, The Summoner was able to take control again, just for a brief moment. Ciar was trying to capture the Master as the second, but the Summoner managed to pool the last of his consciousness and pick someone whom he knew would defect, given the opportunity. That person was Takeshi, and he was able to control Ciar just long enough to get him, knowing that Ciar could only take two people as its Acolytes.
(If this section feels kinda rambly or repetitive, it's because I wrote this just before bed. XD)
Ciar, the beast itself
Ciar is a being of pure dark energy. It is approximately 15 feet tall upright. It has a somewhat humanoid form, but will usually stand hunched forward like a beast. Art-wise, it will seem mostly two-dimensional, with jagged edges and very little definition, mostly all black. The only part which isn't black is its eyes, which glow a sinister yellow. It has an underbite accented by a sharp, triangular-shaped jaw, and its claws will cut through titanium and break diamond.
No physical attack can harm it, no physical barrier can stop it. Energy barriers can faze it a little, but it will invariably get through. It prefers not to deal with pesky humans and their futile attempts to destroy it, so it usually will travel in secluded areas.
Only magic has any chance to destroy it, but nobody has the power necessary to cause any harm but the Akari. Even then, they are permanently affected by Ciar's Curse, which causes any magic cast upon it by a single member of the Akari to be entirely ineffective. In addition, although their magic can hurt it, the Curse causes anything which could possibly kill it to fail. To make matters worse, the very sight of Ciar causes fear to overwhelm any single member of the Akari. The only way they have to deal with it is for at least three Akari, born under the bloodline or bound by marriage, to come together and seal it.
The only person who can destroy Ciar is one with an incomplete bond with the last-born Akari, one strong enough to allow that person to produce Light's Edge, a blade of pure light which manifests itself upon that person's dominant arm. (Therefore, lefties, on the left, and righties, on the right. Azure is right-handed.)
Ciar's primary objective is to destroy the last-born Akari, therefore exacting its revenge upon the family, and destroying the world's only chance at keeping it under control. In addition, it will destroy any other Akari it may find, so to lessen the chance of it being sealed away. Once it has done so, it will proceed to destroy...well, everything, and cause the world to fall into darkness. The Shadow Acolytes will be summoned again, and open a demonic rift to further the world's descent into chaos. If this were to happen, who knows if the world would ever recover...?