Kirei Kotomine

Kotomine Kirei (言峰 綺礼) is a character from Fate/stay night.

Through an agreement between the Mages' Association and the Church, the Holy Grail Wars are moderated by a priest. Kirei's father was the mediator for the 4th Holy Grail War, and when he died, Kirei felt obligated to replace him. His selection as mediator is unusual, for Kirei is a member of both the Church and Mages' Association, organizations on hostile terms with one another. Since the death of Rin's father, he has also acted as an indirect caretaker for Rin. Although ranked lower in the Church hierarchy than Ciel (from Tsukihime), Kirei employs many of the same techniques and weapons she does.

Profile
The mediator dispatched by the two big organizations: the Association and the Church.

Has the qualifications of a Church Executor and specializes in healing by spiritual mediation. 1st class as an Executor, but still can't match the seventh of the Burial Agency. But, attack power against spiritual bodies is superb (while twisted) and represents how unshaking his faith is.

Thought to love destruction, but just like Shirou, he's the "creator" type of magus. Skill at fixing the spiritual/mental body is at Bishop level.

Not a villain but an evil person. Not inhuman but deviant. The biggest enemy in Fate saga, the final boss in stay night (Saber route and Sakura route) and Zero. If Archer is a light embossing of Shirou's defects, then Kotomine could be said to be the wall exposing those defects by darkness. Like Shirou, a void human being.

Initial concept was "the guy that you just knew the first time you met him, to be the one pulling all the strings".

History
Kirei was not only a Master in the 4th Holy Grail War, but was also responsible for the monstrous conflagration in the ensuing turmoil following the war's end. He has lived a troubled and gloomy life, hounded by guilt and sorrow. Although Kirei understood the distinction between good and evil, he could only revel in committing sins. Like his father, Kotomine Risei, Kirei became a vicar, but he was trained as an exorcist and had an ironic talent for healing other people. With no alternative, Kirei prayed that, through marriage to a woman he loved, he could finally achieve respite from his tortured existence. When Kirei discovered marriage could not change him, he was on the brink of suicide; his ill wife, filled with concern, committed suicide to show to Kirei that he could still feel compassion for others. However, after her death, Kirei was disgusted to realize he would have preferred killing her instead; from that day on, he ceased pursuing salvation altogether.

As a representative of the Church, it is initially implied that Kirei summoned an Archer and gained entry into the 4th Holy Grail War, being one of the survivors.

In the aftermath of the fourth war, Kirei became curious as to the capabilities of the Holy Grail; he decided contingencies in case another war began during his lifetime. After the Fuyuki fire died down, Kirei rounded up the surviving children and imprisoned them within the basement of his Church; he then allowed his Servant to consume their souls and stockpile Mana. While Archer took up residence in Fuyuki City, Kirei joined and participated on several missions for the Mage's Association, additionally acting as a distant supervisor for Rin Tōsaka. Nearly a decade after his death, Kirei was designated as Manager of the 5th Holy Grail War; at his request, Bazett Fraga McRemitz, a sorcerer-hunter Kirei met on one of his assignments, joined him in the conflict. Kirei then murdered Bazett, stealing her Command Mantra by slicing off her left arm. Using these mantra, he formed an additional contract with Bazett's now orphaned Servant, Lancer.

Fate/Zero
Kirei actually summoned Assassin while Tokiomi Tohsaka, Kirei's mentor, summoned the Archer-class Servant. Gilgamesh "kills" one of them in full view of the other Masters and the Assassins initially acted as reconnaissance agents for Tokiomi and Kirei.

Kiritsugu recognized Kotomine as being the most dangerous of the other Masters from the start and Kotomine knew about Kiritsugu well enough to be interested on him. During the first days of the war, Kirei followed Tokiomi instructions and stayed in the church as "defeated Master", but the growing interest on Emiya Kiritsugu lead him to search for him, engaging in some encounters against Kiritsugu's assistant Maiya and his wife Irisviel. Kirei won against them while Kiritsugu was fighting Kayneth Archibald El-Melloi, but seeing that Emiya Kiritsugu was a being that could be comprehended by others and not an empty man with the answers he sought, dissapointment grow on Kirei, and he retreated.

Intrigued by Kotomine Kirei's participation in the war, Gilgamesh suggests that to overcome his emptiness, Kirei should determine backgrounds and the motivations of the other Masters and Servants as to why they wish to obtain the Holy Grail. Then, he decides that he should observe Matou Kariya’s fate too.

After Caster's fight at the Mion river, Kirei brought Kariya to Matou's underground worm chamber and leaves, only to find the dead body of his father back at the Church. Kirei finds a dying message from him; a secret password that gives Kirei all the remaining extra command matra. Kirei sheds tears after seeing that his father cared about him till the end, but he was feeling the exact opposite affection that a normal human being should. He wanted to see him die, just like when his wife died.

Kirei goes back to his room and has a conversation with Gilgamesh, but this time, Kirei is the devil tempting Gilgamesh. Kirei explains him how Tokiomi will use his last Command Spell to kill his own Gilgamesh and open the gate. Seeing this, Gilgamesh accepts Kirei's plan to kill Tokiomi and take his position as Archer's Master. Tokiomi invited Kirei to his house one last time before Kirei headed back to the Church headquarters. Tokiomi whole heartedly thanked that he was a loyal apprentice to him and gave him an Azoth knife to him as a parting fit. However, Kirei backstabbed him with that knife.

Kirei made a deal with Kariya that if he helped him, Kirei will arrange a meeting with him and Tokiomi and also in return for kidnapping Irisviel von Einzbern using Berserker in the guise of Rider, he is promised victory and the Holy Grail. Zouken appeared in front of Kirei and says he must be plotting something interesting. Sensing Zouken as a dangerous threat, he attempts to kill him on the spot but Zouken can't be killed by just being pierced by Black Keys. Zouken chukles at him saying he feels the same kind of broken personality just like himself as he left. Kirei determines he's one of the enemies that he needs to kill one day. As Zouken said, the "meeting" of Kariya and Tokiomi was a event arranged only to Kirei's amusement, as Kariya finds Tokiomi already dead and Aoi walks in on him, misinterprets the situation and blame Kariya for her husband death. Kariya strangles her, as Kirei and Gilgamesh enjoy the scene.

Kirei transferred his hideout to the underground sewers where Caster used to be, set Irisviel as the vessel to the grail, order Gilgamesh to go out and intercept the enemies that are coming this way and Kariya's Berserker to fight Saber.

Kiritsugu and Kirei finally have their fateful fight at the center hall. They have nothing to say to each other. Kirei performs Ba Ji Quan mortal blows on Kiritsugu, but Avalon quickly heals his body and the Magus Killer makes a comeback with his Innate Time Control. Kirei tosses all his remaining black keys in a spin, so that they will be right over Kiritsugu just as Kirei gets to him - Kiritsugu can either try to dodge sideways or backwards and get punched anyway, or jump away and get slashed by the keys. Instead, he just stands there, reloads, and shoots Kirei just as Kirei's fist connects and crushes his skull. With the battle in stalemate, the black mud gushing out from the holy grail in the room above engulfs them.

After a grail induced dream, Kiritsugu points his gun at Kirei's heart from behind and Kirei wakes up too. Kirei's surprised why Kiritsugu didn't accept the offer of the holy grail. Kiritsugu's answer was that it sacrifices too many things for what it gives. Kirei says that he want it even so and Kiritsugu shot him in the heart saying that he don't understand Kirei.

In his last moments, the Holy Grail appeared to Kirei; filled with hatred and envy for Kiritsugu, he reached out and touched the cursed artifact. Kirei prayed for an end to humanity; his wish was granted in the form of fire. Amidst the roaring flames, Kiritsugu's Saber obliterated the Holy Grail, allowing its tainted water to soak Kirei's lifeless body, resurrecting him with an artificial, black heart. Kirei wakes up and find Gilgamesh near him. He seemed to have gained a flesh body from something that flowed to his body through the Master and Servant connection. After looking at the burning town, Kirei laughs out in pleasure. He finally realizes what brings happiness to him in this world.

Half a year later, coming up with a plan to entertain himself, he gives Rin the Azoth knife that killed her father as a gift, saying he received from her father upon completion of his training.

Fate/stay night
Kotomine Kirei is an antagonist in all three scenarios of Fate/stay night, though he is the absolute villain only in Saber route. Kirei is almost always the first to have access to the Holy Grail, though he cares little for it himself; he is more interested in the results of wishes made upon a tainted artifact, especially with individuals who possess pure souls or good intentions.

In Fate, he aparently remains out of the plot until nearly the end. Shirou goes to Kotomine's place again hoping to get another advice but he finds out he was the master of not only Lancer, but Gilgamesh as well. He reveals that he has been keeping Gilgamesh from the previous war. Since then, he was using orphans from this fire incident to supply Gilgamesh with Mana. He uses the Grail as bait to tempt Saber and Shirou into using it, but they refuse. In the final day of the war, Kirei and Shirou fight in a cataclysmic final battle, the same as Kirei and Kiritsugu ten years ago. Shirou and Saber (fighting Gilgamesh) use Avalon at the same time and defeat their enemies. Ironically, the knife that killed Kotomine Kirei was the same Azoth knife that he gave to Rin.

In Unlimited Blade Works Kirei's goals are unchanged, but he also lends his Archer to Matou Shinji. His plans are truncated when he's killed by Lancer shortly after forcing Lancer to stab himself.

In Heaven's Feel route, he finds in Matou Sakura a way to find the answer to what he was looking all his life. The "training" that Matou Zouken did to her in the years beteween wars turned her into a Lesser Grail, the Black Grail of Makiri. With her innate connection to the dark being that sleeps within the grail since the Third War, he plans to see the Grail completion and the birth of Angra Mainyu, thanks to the Third Magic. He uses Emiya Shirou's love for Sakura to assure her safety, and when Sakura is tainted by the shadow inside her, Kirei aids Shirou in a raid against her and Zouken to save Ilya, the White Grail of Einzberns. They manage to rescue Ilya, but are confronted with both True Assassin and Dark Berserker. Kirei have to settle a old score with Zouken, so he stalls True Assassin behind and pin him to a tree using the information he got by observing Lancer's last battle, and then proceeds to exorcise Matou Zouken. Afterwards, however, Sakura arrives and stop his black heart, giving him a few hours of life.

Near the end, Kirei suddenly appear, intending to stop Shiro destroying something he has desired to witness. He wonders about the behavior and stability of an entity born of evil. After he gave up on salvation and happiness, he questioned the meaning of his own existence. He questioned how a being like himself was allowed to be born. Kirei sought to find the answer by completing the tainted Grail as he figured that the tainted Grail was a large version of himself and by watching its birth, he would be able to find the answer to his question. Contrary to Kiritsugu, Shirou is, like Kirei, a void human being pursuing hapiness. The only difference is that Kirei was unable to find happiness outside evil, so this fight is also a way to release his frustation and envy. Finally, Shirou notices that he likes Kotomine Kirei, and the two proceed to engage in a fateful fight like the one ten years ago. With their bodies half-dead, the only fight they are able to perform is a hand-in-hand brawl. Kirei "died" a bit before in the forest, so Shirou wins and Kirei falls defeated. As last words, Kirei declares Shirou as the winner of the Fifth Holy Grail War and the last Master, and then his body crumbles lifeless.

Trivia
While fighting Assassin during the Heaven's Feel Arc, Kotomine wields a weapon similar to the Black Keys, swords that another character in the same universe, Ciel uses as well. As both characters are members of the Sacred Church, it is possible that these weapons are a universal equipment of the organization. In Fate/hollow ataraxia it is revealed that Kirei is the father of Caren Ortensia (as Caren's Mother was actually Kirei's late wife who commited suicide because of Kirei).