Kiara Sessyoin

Kiara Sessyoin (殺生院キアラ) is the Master of Caster in Fate/Extra CCC and the game's true antagonist. She is also known as the Devil’s Bodhisattva and the Last Prophet. She also appears as the Beast-class Servant Beast III/R (ビーストⅢ/R) in the Grand Orders of Fate/Grand Order.

Fate/Extra CCC world
Her real name is Kiara Sessyoin (殺生院祈荒). Although she was born as the daughter of the Shingon Tachikawa Eiten School (真言立川詠天流) head, she was bedridden until she was approximately 14 years old due to her illness. She learnt Spiritron-hacking from fellow worshippers. Afterwards she reformed the Tachikawa Eiten School, rapidly increasing the number of believers over the internet and became the leader of the cult. Kiara Sesshouin saved many lost people with the doctrine of Tachikawa-ryu as her foundation. The Church also acknowledges Kiara Sesshouin as a modern prophet, due to a certain opinion of a Cardinal; one of the candidates for the next Pope.

However the virtual religious cult no longer exists. She is the last officiating monk of the barely surviving Shingon Tachikawa school (真言立川流). All of the believers who followed Kiara committed suicide, men and women adored her so much that they killed themselves. People who fell deeply in love, people who were addicted to maltreating her, people who were dependent on conversation with her, people who hated her to death, people who lost themselves in carnality. All with the same result. Suicide. Even offline, people who got involved with her would almost invariably commit suicide. Even virtual police investigators and intelligence operatives from the Western European Plutocracy (西欧財閥) got taken in. According to Julius B. Harwey, the intelligence operative died in order to save her from her adherents who were going to kill her and that individual was antisocial, and not the type to pursue women.

After saving many people, she was betrayed by those she saved. She saved many people, but those same people trampled her good intentions underfoot. She was betrayed by human beings countless times. Yet she never abandoned her resolve to give them salvation. Betrayed by both faith and people, she was slandered as a murderer. It's also a fact that she was the cause of mass suicide and hostilities. Consequently, with the sponsorship of the Western European Plutocracy, she became an internationally wanted digital criminal. She was pursued by both the Holy Church and the Western European Plutocracy. There are people who defended her, but the Plutocracy had the backing of the Holy Church. The Holy Church decided against apprehending Kiara because she was an eyesore, they acknowledged her as the greatest enemy to the preservation of their own faith. Leonardo B. Harwey guesses that the church could not overlook being passed over while some woman in the Orient showed up and got treated like a prophet.

She is also a master who participated in the Moon Cell Holy Grail War, for her own desire in order to save people. She is the reason that BB was unleashed, when she interfered with Sakura Matou's program. She met BB before everybody in the Moon Cell Holy Grail War. She was captured by BB when she was imprisoned by the black noise on the near side. She made a peace treaty pact with BB, BB would spare Kiara's life as long as Kiara never antagonized BB. Thus she was confined to the school. Kiara was being observed by BB, so she couldn’t say anything that would suggest BB's existence.

EMIYA Alter's world
While no details are given, it is mentioned that this incarnation of EMIYA Alter hunted and killed her, but also a lot of her innocent followers, leading to his cold and result-oriented demeanor.

Appearance
She is Japanese and is in her mid to late twenties. Her attire resembles that of a Japanese Buddhist nun; she wears a tight dress with a slit up the left side exposing her leg and a large white habit similar to a hood with a large gold necklace wrapped around it. She claims that her habit of having a slit up the side is because everybody in the school are so distinctive and she wanted to take a risk of youthful indiscretion. Even Gawain considers her to have an amazing body.

After consuming Passionlip, Meltlilith, BB and Sakura her appearance changes to that of a demon. In her new form, Kiara's habit now hangs from the two massive black and pink lined curved horns extending from the sides of her head. Her black hair now flows in twisting locks behind her and on her forehead lays three vertical dots similar to those of Savior. Her attire has become that of a revealing long white coat with belled sleeves and thigh high pink boots. According to Kinoko Nasu, her demon outfit was specifically requested by him to incorporate a "naked apron" theme.

Fate/Extra CCC
When Kiara was first introduced, she assumes the role of Taiga Fujimura; the homeroom teacher of Hakuno Kishinami and Shinji Matou.

After Hakuno shifted to the Far Side of the Moon Cell, Hakuno was tasked to recruit other Masters to join the Student Council and encounters Kiara, who claims to have lost her memories. Kiara tells Hakuno that she has no interest in joining the Student Council, and reveals her servant Caster and refers him by Andersen. Andersen then warns Hakuno not to trust Kiara.

When Hakuno collected all the SG information from Rin Tohsaka, Kiara helps Hakuno to enter Secret Garden to find and face the real Rin.

In the True Route which the player chose to not use SG on Passionlip, Kiara and Andersen revealed themselves to the Alter Ego and mortally wounded her. She then absorbed Passionlip into herself.

Later in the fifth chapter, Kiara starts showing puzzling behaviour such as making herself busy whenever Hakuno tries to make contact with her. She is seemingly killed by Meltlilith when she sneaked up behind Kiara. In the true route however, she survived and concealed herself thanks to Passionlip's presence concealment power.

Following Meltlilith's defeat at the hand of Hakuno and servant, Kiara appeared to Meltlilith who was on the verge of disappearing. The woman coldly told Meltlilith that she won't allow her to help Hakuno and proceeded to absorb Meltlilith's quasi-particle, stating that the Alter Ego's power will be her nourishment.

In the True Route, she reappears when Kiara first absorbs BB when she could not control Moon Cell system. Andersen reveals that Kiara absorbed Passionlip's Ego allowed her fool everybody with her fake death. She traps both Hakuno and their Servant, and used this opportunity to absorb Sakura and fully control the Moon Cell. Caster used Marchen Meines Lebens to allow Kiara to be reborn as the earth mother goddess and reach a state close to that of a True Demon. Caster sends both Hakuno and the Servant to two different locations.

Hakuno confronts Kiara in her Heaven's Hole form. To her surprise, Hakuno's Servant arrives to fight. Normally, no normal human could stand against her but she lost to Hakuno due to the girls that were absorbed, wanting to protect their love for Hakuno and resisted inside her body. Caster scorn her, calling her an idiot that charged right into the fight with no regards to that one weakness. She dies saying that she was not defeated by a Hero nor a Savior but by women like her.

Fate/Extra CCC Fox Tail
Kiara was killed off by Saber and Kazuhito Sakagami.

Fate/Grand Order
Appearing in the event Deep-Sea Cyber-Nirvana, the initial indication of her existence is the SE.RA.PH turned oil platform takes on the shape of her body. It is later revealed she is the psychiatrist hired by Seraphix to care for mental well being of the staff. Given a church as her office, she enjoyed helping people and glimpsing the secret behind Seraphix.

She was later possessed by one of the Demon God Zepar who escape the Time Temple, and willingly gave her body as a sanctuary. Combining with the Demon God allowed her to see through the Multiverse including herself in CCC, causing her to formulate a plan to save humanity based on this "experience". Her overwhelming desire ultimately subdued the Demon God, and succeeded in turning Seraphix in to virtual space, becoming Beast III/R, infant stage of the Beast.

SE.RA.PH. - Deep-Sea Cyber-Nirvana, Epic of Remnant: Extra
She was first encountered when she pretended to be Marble Macintosh.

Chibichuki!
She is a teacher in charge of Japanese. When she first introduce herself, she jokes about being in charge of health and physical education. She used Hans Christian Andersen's literature as her teaching material. She overanalyzed with sexual innuendo interpretation.

Other appearances
In Type-Moon's April Fools' Day 2015, Kiara is part of the Imperial Roma talent agency and her idol name is Chiara Dan (壇キアラ). Her class is Soothing Saint Idol (いやし系聖女アイドル). She was born in Japan and debuted in 28 March 2013. Her hobbies consist of Reading, Reciting, Writing Sutras and Salvation. She likes someone who is sinful and her message is "Both young and old are all the same".

Human
Thesis of the Still Heart is a Codecast skill that allows her to access someone's Secret Garden. The five meditations are meditation on impurity, meditation on compassion, meditation on cause and effect, meditation on separation from the world, and mindful breathing meditation. It finds the openings to a person's heart, and exposing the backwaters that the person themselves is not even aware of. It’s a basic meditation method to renounce worldly desires. It's more like exposing the affected areas than seeing through it. The Thesis of the Still Heart is medical software. It finds the patient's injuries, and cleanses the stagnant areas. The shield is a wall of the heart that guards secrets. Therefore, if we uncover the secrets, there will no longer be any meaning in protecting them. Kiara compares the codecast to a vaccine, if the wall of the heart is an illness, the Thesis of the Still Heart is a vaccine to treat it. Although Julius believes it to be more like a virus. Kiara said that it is ineffective for AI such as Sakura because only human beings can read emotions and they can't understand emotions.

It is also the creator of her other Codecast Ten Thousand Colored Stagnation that allows people to enter the hearts of others. It is a dangerous codecast, since the network became the basis of human society, this power to control others through it is essentially the power to rule the world. It is the secret technique of the Tachikawa Eiten school, Ten Thousand Colored Stagnation is a codecast that is considered the greatest crime in virtual history. A forbidden art that drove many people mad and destroyed them.

Heaven's Hole
With Kiara absorbing Passionlip, Meltlilith, BB and Sakura Matou and through Caster's Noble Phantasm and the Moon Cell, she reaches a similar existence to a True Demon and Saver. She is the enemy of the enlightened (Buddhas). Her existence is similar to a certain man-made demon who had once been demonized and celebrated as a sacrifice to prove the evil of mankind. She is known as Heaven's Hole (ヘブンズホール) and gains the Noble Phantasm Angra Mainyu/CCC and Sukhāvatī - Heaven's Hole. Its formal name is The Third Pleasure Heaven of Deeply Grateful Existence (随喜自在第三外法快楽天). She is a new god descended from the Covetous Mother Goddess. Only Saver, who has by all rights mastered the esoteric ability to completely turn off his sexual desire, is able to match up to this woman incarnate.

While Caster is unsuited to fight, Kiara personally fights in close combat while Caster supports her.
 * The Principle Fist Mudra (胎蔵界　理拳印) - She makes several hand seals to use this self applied skill. It grants enemy's ATTACK skill sealed, HP absorption effect to GUARD and stun effect on BREAK.
 * The Wisdom Fist Mudra (金剛界　智拳印) - She makes several hand seals to disable any attacks and causes MP damage.
 * Daizushi Chiya kanpō - She creates an energy orb from her hands; as the orb levitates, it fires energy rain on the enemy and causes damage.
 * Eitenryū - (詠天流・四念回峰行) - Causes damage and paralysis.