Index Librorum Prohibitorum

Index Librorum Prohibitorum (禁書目録 Kinsho Mokuroku (Indekkusu)?, lit. "Index of Prohibited Books") is the eponymous character of Toaru Majutsu no Index. Commonly known as Index, she is the main female character of the Magic Side; in Toaru Majutsu no Index series. She is a member of Necessarius and has Perfect Memory and is not poisoned by the effects of reading grimoires. As such, she holds within herself 103,000 magical grimoires at the beginning of the series.

Etymology
Her name is based on the book with the same name, Index Librorum Prohibitorum|The List of Forbidden Books}} or "Index Librorum Prohibitorum"|禁書目録 |Kinsho Mokuroku }} in Japanese. It is a list of publications prohibited by the Roman Catholic Church.

The avowed aim of the list was to protect the faith and morals of the faithful by preventing the reading of immoral books or works containing theological errors, although it also contained scientific works by leading astronomers, such as Johannes Kepler. The various editions also contained the rules of the Church relating to the reading, selling and censorship of books. It was abolished on 14 June 1966 by Pope Paul VI.

Appearance
Index is small in stature, has a petite build, and, much to her chagrin, a flat chest. She has thigh length, silver hair, and large green eyes. She is also often seen wearing her Walking Church, a white, and modified nun's habit with gold highlights. It is an accurate replica of the Holy Shroud of Turin and offered Index ultimate protection from most attacks, however, it was destroyed by Touma's right hand. She still wears it, though safety pins are now needed to hold it together.

Personality
Due to being raised in a church and having no memories of her life up until a year before she met Touma, Index is quite innocent and naive, often being elated by things that an adult or even people her age would find mundane. She is slightly ignorant and curious of modern technology, not knowing what a touchscreen was or how it worked until Kazakiri Hyouka showed her.

She is very gentle and polite with people and has a kind nature, as shown when she picked up a stray kitten and took it home, although Touma initially refused. She also, like Touma, has the trait of sacrificing herself for others sake which is why several people befriended her in the past who still keep caring for her despite her memory loss each year. Despite her naivety, Index is extremely intelligent, as a result of having the knowledge of 103,000 grimoires stored inside her. Due to her photographic memory, Index is able to remember everything in the books and often gives Touma information when needed.

She can be easily irritated especially when it comes to Touma, who usually ends up angering her in some way as a consequence of his own bad luck. He is often bitten by Index as punishment. It is a recurring gag for Index to bite Touma whenever he has inadvertently annoyed or irritated her in some way (much like Misaka Mikoto's habit of trying to electrocute him whenever she is annoyed at him), occurring even in serious situations or in front of important persons. She has even bitten him out of anger for trivial things that he has not even done. At one point, Touma even compares her to a mosquito. However, in Toaru Majutsu no Index no Subete, it is noted that it is a sign of affection towards him, as Touma is the only person whom she bites. Index can also be rather bratty at times, often getting annoyed when Touma doesn't spend enough time with her.

She also has an extreme appetite as shown when she met Accelerator and made him to spend all of his money treating her to food. In fact, the very first thing she said to Touma was that she was hungry. Index has taken a liking to the anime Magical Powered Super Android Girl Kanamin and once cosplayed as her. She has strong feelings towards Touma and even confessed her love after knowing Touma lost his memories because of her, however he avoided answering by changing the subject of the talk since he has no idea about what kind of feelings he used to have with Index.

Background
Much of Index's background is currently unknown because of the periodic memory loss that was brought upon her. Although, Index states that she was born and raised in St. George's Cathedral, there is not enough evidence to corroborate this, as Index as well is unsure of it.

It is not known if 'Index' is her true name or if it is a name given to her because she holds within her the 103,000 grimoires. It is confirmed that Index was specifically chosen as the vessel for the 103,000 grimoires because she has the ability to perfectly memorize things and also because she is unaffected by the books' debilitating effects. She possesses no mana and therefore cannot use the grimoires. She is accompanied by Stiyl around the world in order to memorize grimoires, from the Pataliputra ruins to the Vatican Library.

Later, after becoming the vessel of the grimoires, she was given partners as a means of protection. Three years prior to the start of the series, she was the partner of Aureolus Izzard then a year later, Stiyl Magnus. Index's relationship with her partners is unknown because of her periodic memory loss, but it is implied that both Aureolus and Stiyl cared for her deeply. In Aureolus' case, he was Index's teacher during his time with her. It is confirmed that Kanzaki Kaori were best friends with Index before Index's memory was erased.

The church told lies to Kanzaki and Stiyl regarding the true nature of Index's memory being erased, as they planned to make the grimoires harder to access as well as because of their fear of Index betraying them or her apparently becoming a Magic God. The church implanted a Collar and a multi-layered program that would disable her from using the magic of grimoires, as such she cannot access her mana, and therefore use magic, normally. To complete this defense, the Collar made Index extremely ill, and required an annual erasure of her memories.

Lola Stuart was the one that came up with this plan, as the alternative was to cut off all of Index's limbs and lock her inside the Tower of London to ensure absolute safety of Index Librorum Prohibitorum's knowledge from magicians that would misuse it, and to prevent her escape.

Index came to Japan a year before the start of the series, although she had already lost her memories prior to arrival, and has somehow awoken in a back-alley with at least basic knowledge regarding her position in the magic side. This was done as part of Stiyl and Kanzaki's plan to keep Index away from magicians that would misuse her knowledge, as Japan was seen to be a place with little history of magic according to them. Both Stiyl and Kanzaki believed it was for the best if Index spent the year running away from magicians as opposed to living through a year full of happiness, as then it wouldn't be as painful (for both themselves and Index) when her memory had to be erased. Index eventually ended up in Academy City as she was being chased by Stiyl and Kanzaki, because it was once again time to erase her memories. Moving from rooftop-to-rooftop during Academy City's unforeseen power outage, she slips and falls, landing onto the apartment balcony of the ever-unfortunate Kamijou Touma.

Toaru Majutsu no Index
Being the main heroine of Toaru Majutsu no Index, Index has a large role in the events of the story, alongside Touma.

Shinyaku Toaru Majutsu no Index
Due to the story shifting focus from magicians chasing her down for her grimoires (though this is apparently still something that occurs occasionally) Index takes more of a backseat role for the GREMLIN Arc which opened Shinyaku Toaru Majutsu no Index only reaching the role she had in Old Testament in the closing of the Arc. Though she takes her role as a main heroine again in the second overarching arc; the Fall of Academy City Arc, aiding Touma in battles and serving as someone he tries his hardest to protect alongside the Magic God Othinus.

Abilities
Despite normally not being able to use magic, Index has a magic name, Dedicatus545, "The dedicated lamb protects the knowledge of the strong"|献身的な子羊は強者の知識を守る|Kenshinteki na Kohitsuji wa Kyōsha no Chishiki o Mamoru}}. As the vessel for 103,000 magical books, she is unable to use conventional means to cast spells; instead, she can only use abilities which intercept opponents' spells.

Perfect Memory
Perfect Memory|完全記憶能力|Kanzen Kioku Nōryoku|lit. "Capability of Perfect Memorization"}}: Index is capable of perfectly memorizing anything, which is one of the reasons why she was chosen as the vessel for the 103,000 grimoires, magic books that are poisonous to the mind. This made Yamisaka Ouma wonder if Index is even human.

Not only that, but she has powerful analytical skills, able to examine a 30 fps anime easily, as well as making her able to reconstruct an image on a surface, like a balloon or bottle, even after it is destroyed.

Abilities-related to being the Index Librorum Prohibitorum
Index also has abilities that require no mana whatsoever, for they are not of magic, due to the knowledge that she has from the 103,000 grimoires inside of her. This allows her to minutely to pin-point the weaknesses in the spells of others better than anyone in active combat, and later use it against magicians, such as what happened to Angelene, and her poor usage of her magic coinbags in their first battle.

Spell Intercept
Spell Intercept| 強制詠唱 (スペルインターセプト)  |Kyōsei Eishō (Superu Intāseputo)|lit. "Force Chant"|yenpress = Spell Interception}} uses Notarikon codes, a quick Kabbalah reading method that uses only the first letter of a word, to hijack the spell formula that the caster has been conjuring in their head and cause the magic to go berserk or be outright cancelled.

Singing
Singing is a fundamental part of Index's abilities. Using her knowledge she gets from the 103,000 grimoires, Index uses her songs to break down spells and things similar to them. For example, Index uses her singing to eliminate the virus that plagued Last Order's mind, which allowed the Imaginary Number District and Fuse Kazakiri to manifest in Academy City.

A specific form of singing, |Sheol Fear| 魔滅の声 (シェオールフィア)  |Mametsu no Shō (Sheōru Fia)|lit. "Voice of Defacement"}} is an ability in the form of choir that points out and impeaches the contradiction of the basis of the religion or theory of magic that has been cast and causes a break down in the enemies mind. This can be bypassed if there are belief systems nearby, such as an Amakusa Christian near a group of Roman Catholics, or when the intended target cannot hear it, such as when the Agnese Force nuns jabbed their own ears to block off the sound.

John's Pen


John's Pen| 自動書記</rb> (</rp>ヨハネのペン</rt>) </rp> |Jidō Shoki (Yohane no Pen)|lit. "Automatic Secretary"}} is referenced by Index as her "awakening." Here, her voice becomes machine-like and toneless. Her speech becomes blunt and to the point. It appeared when Index's life was in a dire situation, and seemingly makes her immune to pain. She cannot perform magic at this point, and it seems that it's only purpose is to take over Index's body, when she herself cannot do it, like an Automatic Secretary.

Defense Mode

According to Index, she is incapable of magic, however, when under John's Pen's defense Mode, she is capable of accessing the grimoires in her mind. It is unknown whether or not she was capable of performing magic before losing her memories.

After Touma negated the Collar symbol put inside her mouth that was meant to kill her, the defense mode activated. Her voice retains the machine like characteristic, and her methods in eliminating enemies is machine-like. While in John's Pen Mode, she was capable of using several very powerful spells:
 * St. George's Sanctuary| 聖</rb> (</rp>セント</rt>) </rp> ジョージの聖域|Sei (Sento) Jōji no Sei'iki|lit. "Sanctuary of St. George"|yenpress = St. George's Hallowed Ground}}, a high class defensive spell which distorts space-time.
 * Dragon Breath| 竜王の殺息</rb> (</rp>ドラゴン・ブレス</rt>) </rp> |Ryūō no Satsuiki (Doragon Buresu)|lit. "Killing Breath of the Dragon King"}}, a high class offensive spell that has the same amount of power as the legendary dragon of Saint George. This spell casts a beam of light at the target, destroying everything in it's path. It has been shown to have very long range, such as when it destroyed Academy City's satellite that housed the supercomputer, 'Tree Diagram', in outer space. The first level of this spell is enough to surpass the cancelling speed of Kamijou Touma's Imagine Breaker and the second level is enough to blow away Innocentius with ease. The after-effect of this spell is the Feather of Light.
 * Eli Eli Lema Sabachthani| 神よ、何故私を見捨てたのですか </rb> (</rp>エリ・エリ・レマ・サバクタニ</rt>) </rp> |Kami yo, naze watashi wo misuteta no desu ka (Eri Eri Rema Sabakutani)|"Lord, why have you forsaken me?"}} - Is a powerful anti-Christian spell which throws a powerful bloody-red beam of light.


 * Scarlet Stone of Pexjarva|ペクスヂャルヴァの深紅石|Pekusujaruva no Shinkuseki|yenpress = Crimson Stone of Pexjarva}} - This spell causes the bones in the target's feet all the way up to the knees to feel a deep pain started to swell up. This feels like the joints between the bones being forcibly stretched apart. This invisible attack seems to be coming up from the floor and seeps into target's body from there.
 * Sulfur Rain will Scorch the Earth|硫黄の雨は大地を焼く|Iō no Ame wa Daichi o Yaku}} - An area spell attack that makes around 50 arrows appear from above. These arrows strike down like guillotines, piercing and burning through the target. Just one arrow alone is enough to turn stone into dust.


 * During Index's stay in St. George's Cathedral while she was being restrained by Stiyl Magnus, she grows crimson wings, which are said to be angelic wings. With them she could dissipate Innocentius and blow his user away by just flapping them.
 * Index has also displayed the ability to summon legendary weapons and artifacts creating multiple copies of the same and use them to attack, all of them 'being able to suffocate the enemy just by floating in the air', some of the weapons mentioned are:
 * The Sword of the Harvest God |豊穣神フレイの剣|Hōjōshin Furei no Ken}} or Sword of Victory, the magic sword of the god Freyr from the Norse Mythology, which the legends said that if someone wise possessed it, it would fight on its own and bring about victory for its owner.

Information transfer
Index is able to use the knowledge in her mind to make a Gungnir lance. In order to recreate the phenomenon, a magician of great power, skill, and mental discipline is needed to focus its power. By transferring the necessary information to Leivinia needed to draw out the design of the phenomenon from. By singing at ultrasonic frequencies necessary to keep the weapon formed, this continually exposes Leivinia to the knowledge of 103,000 grimoires through the singing putting her constantly in danger of succumbing to them poisoning her mind. Interrupting Index's continuous singing however would immediately result in the destruction of the lance. If it successfully imitated the phenomenon of throwing lance, it would likely destroy the world.

Indeed, Index doesn't need to sing to transfer a thought into someone's head. She can use a high-speed incantation, likely Notarikon, by merely moving her lips.

Other abilities
In Shinyaku Toaru Majutsu no Index SS, Index is able to read the contents of the Book of the Dead, and accurately mimic the voice of the person for whom the Book of the Dead is written for. It allows her communicate its contents with tone and feeling that perfectly matches that of the mimicked person. However, due to the unique property of the Book of the Dead, a grimoire that is different for each person a book is written for, it is likely an intrinsic part of the book and not one of Index's abilities.

Kamijou Touma
At the beginning of the series Touma saved Index from the fate of having her memories erased every year and she has been living with him ever since. She is in love with him but it is unknown if he feels the same towards her. She gets mad at him for going off to fight magicians without her and constantly turning up with new girls, and usually expresses her anger by trying to bite him. Index is still the only girl to have confessed her love to Touma, however, Touma avoided answering by changing the subject of the conversation since he had lost his memories, he had no idea about what kind of relationship he used to have with Index. Moreover, Index is also the first and one of the only girls known to have kissed Touma, the other being Shokuhou Misaki. This happened when she tried to bite him during the Daihasei Festival Arc, which caused her much embarrassment. In the Miracle of Endymion movie, Index mistook Arisa's question and describes her relationship with Touma to Arisa as one where Touma just feeds her.

Tsuchimikado Maika
Maika is Index's friend and the person she usually spends time with when Touma is away at school.

Kazakiri Hyouka
Kazakiri is a very special friend of Index's. They met during the Kazakiri Hyouka Arc and clicked right away. Even after learning that Kazakiri isn't human, Index didn't look at her any differently and they stayed friends.

Misaka Mikoto
Index considers Misaka as a rival in love for Touma. After their first meeting, both fought over who would stay with Touma. Both knew that Touma usually ends up in situations where he usually saves a girl's life and were angered at him when they found he saved the other girl's life. She also considers Mikoto to be lacking manners compared to Mikoto's clone, Sister 10032. Also, Misaka is embarassed to note that Index knows more about Japanese culture than she does, despite being a foreigner.

Kanzaki Kaori
Kanzaki and Index were close friends before Index had her memories erased. After Index had her memories erased Kanzaki tried to make more memories with her again, but after a while she gave up on this and allowed Index to think that they were enemies. Even though Index no longer remembers her, she is still very important to Kanzaki.

Stiyl Magnus
According to Kanzaki, Stiyl and Index were close friends before Index had her memories erased, but after witnessing her memory erasure each year, he and Kanzaki gave up on making more memories with Index and allowed Index to view them as enemies. As a result, despite the problem’s resolution, Index is still wary of Stiyl. The latter's antagonistic manners toward Kamijou Touma only serves to reinforce this fact. On one occasion, Index refers to him as a "despicable man” for his tendency to involve Touma in the Magic side’s affairs.

Meigo Arisa
Meigo chronologically meets Index prior to the "Miracle of Endymion.", and they are apparently friendly enough with each other to have a nice dinner out at a certain family restaurant.