Tatemiya Saiji

Tatemiya Saiji (建宮斎字) is currently the Substitute Supreme Pontiff of the Japanese-based Amakusa Catholics, leading the sect in behalf of Kanzaki Kaori, who vacated the position of leader of the Amakusa. He and his group became involved in the retrieval of the Roman Catholic nun named Orsola Aquinas, and has encountered battles against the Roman Catholic Church, especially the forces of Agnese Sanctis.

After assisting selected agents of the Anglican Church, Saiji integrates the Amakusa Catholics into the Anglican Church, and continues to act as allies to Kamijou Touma, who is regarded by the Britain-based sect as a valuable asset.

Appearance
Saiji has impressionable pitch-black hair and a unique sense of fashion. He wears very loose clothing — an over-sized shirt with a red cross (i.e. a St. Andrew's Cross) to symbolize his position a temporary pope of Amakusa, and a pair of baggy denim pants — and wears shoes with one-meter-long laces. There are also four battery-operated fans that hang on his neck like a pendant necklace.

Personality
Tatemiya is a person who doesn't need a reason to save people, a principle which he implements throughout the Amakusa Catholics. He wants to rebuild the Amakusa Catholic Church into something that can be called a home to Kaori, their Pontiff, so she doesn't need to leave them again to protect them from getting involved in incidents due to her powers of a Saint. He is also able to inspire those that follow him, with either being rude to the point of enraging others, or providing example and referring to how Kanzaki taught them to live.

Orsola Aquinas Rescue Arc

 * Main article: Orsola Aquinas Rescue Arc

Saiji and the rest of the Amakusa Catholics were on a pursuit of a woman named Orsola Aquinas of the Roman Catholic Church. Stiyl Magnus, a representative of the Anglican Church, suspected that Saiji and his group have kidnapped Orsola Aquinas and the Book of the Law to achieve ultimate power. However, the truth was that they were trying to help her escape, but she could not trust them as they were melee fighters who carried weapons. The Amakusas continued on their pursuit of her and eventually recaptured her in an encounter with Stiyl Magnus, Index and Kamijou Touma, who represent the Anglican Church, and the Agnese Forces led by Agnese Sanctis on a neighborhood just outside Academy City gates.

In order to escape their pursuants, Saiji utilized a magical portal located on the nearby Parallel Sweets Park and waited for the exact time they could use the portal to teleport away from the scene. However, the Amakusas' location was spotted by the two forces.

Saiji confronts Touma and Stiyl who puts up a good fight as well as voiding everyone's attack. But he is defeated by Touma and Stiyl who ram into him and binding him through Stiyl's runes. While in custody he has a chance to talk to Touma and Index, trying to convince them that they are not the enemies, rather, the Roman Catholics were as they wanted to kill Orsola Aquinas, and that they did not want to disappoint Kanzaki again after all the people who sacrificed themselves for her sake. Touma and Index then hear the distressful cry from Orsola and suspect something strange about the situation. Then Lucia and Angelene appear to take him in for judgment. But Touma sakes for the truth and accidentally touches Lucia who becomes hostile and tries to kill him. Saiji attempts to move, but is magically bound and cannot. Index helps Touma out of his situation and the two nuns retreat.

Queen of the Adriatic Sea Arc
After the integration of the Amakusa Catholics and Orsola Aquinas into the Anglican Church, they decided to help out in preparing Orsola's move from her house in Chioggia in Venice to England to accommodate in the church's dormitories there. During this time, Index and Touma, who are on vacation, ends up in Orsola's doorstep as well.

During the packing of Orsola's belongings, Saiji and the others began their plan of moving Itsuwa and Touma closer together by suggesting her to give hot hand towels to him.

That night, the Amakusa received a distress call from Index, who is separated from Touma and Orsola during an ambush attack from the Roman Catholic Church and the summoning of the Queen's Fleet, which made reaching the two a difficult task. In the rescue mission, the Amakusa stealthily close in on the Queen's Fleet by using wooden submersibles, which they later use in retrieving Touma, Orsola and sisters Angelene and Lucia, who are captives of the Queen's Fleet from a brutal bombardment in the middle of the freezing waters of the Mediterranean.

Saiji, after preparing a feast for his men and his newest allies, prepare a counterattack, this time to rescue Agnese Sanctis who, along with the entire Agnese Forces, are held captive following their failure to exterminate Orsola Aquinas. Using shock and awe tactics, he infiltrated the Queen's Fleet with the entire force of the Amakusa Catholics while Touma, Orsola and Index locate Agnese's location.

After a tense battle between Touma, Orsola and the Queen's Fleet's commander Bishop Biagio Busoni on one side of the battlefield and between the Amakusa and the Agnese Forces on the other, the entire Queen's Fleet is sunk. The Agnese Forces, their leader Agnese, Touma, Index, Orsola and the Amakusas leave the battlefield with minimal injuries, and Biagio Busoni is surrendered to the Anglican Church.

Acqua of the Back Arc
He along with the other Amakusa try to protect Touma from Acqua. After they are defeated he rouses the troops and unintentionally inspires Itsuwa into an uncharacteristic frenzy.

New Testament: Homecoming
He is seen trying to calm down Itsuwa who is dealing with the revelation of Touma being alive by offering to spar with her. Sister Lucia and Angelene then observe hoping to see actual sword-edge catching, which they oblige jokingly, and fail. This then turns into a matter of pride and it reaches the point where they use an actual japanese sword said to be able to cut through 1000 sheets of paper.

Abilities
He is an expert in Amakusa-Style combat and wields a 180-centimeter-long side-sword with a wavy flame-like blade. He also knows Anti-Impact and Anti-Flame spells, shown in volume 7, among many others that the Amakusa uses.

Design evolution
Saiji's design remains fairly static throughout the series. His design is based on the "clergy" version, as Haimura put it, of the style usually taken up by the B-kei Japanese fashion.