Touma Kamijou is the main protagonist of the Toaru Majutsu no Index anime and light novels and an important character in the Toaru Kagaku no Railgun anime and manga.
By all accounts Touma is an unremarkable tenth-grader in Academy City with a power rating of Level 0 - one which belies his dreaded power, Imagine Breaker, with which he can cancel any power—magical, esper or divine—with his right hand alone, but also at the expense of his luck. Possessing a strong sense of justice, he helps anyone in need and will not hesitate to challenge stronger opponents, even if he has to protect erstwhile enemies. This willingness to help those in need has resulted in him receiving the affection of many women.
In the AWA fics, Touma is a student at the AWA Academy and is part of Class 2.
In the TWA fics, Touma is one of the major characters. Touma is part of the Honor Fighting Force and is a member of The Ragtag of Heroes.
His most striking feature is his spiky black hair, apart from which he looks like an ordinary high school student. It's been mentioned that his spiky hair isn't natural, but was made that way using hair gel after seeing it on a fashion magazine a while back. He also has black eyes (dark blue eyes in the anime and some promotional material).
His father remarks that Touma looks just like his mother when he is worried about something or is thinking deeply.
Because he resides in Academy City, Touma is often seen wearing his school uniform along with an orange T-shirt underneath it. This applies to both the summer and winter versions of his uniform (though when wearing the winter version he doesn't button it). Around the winter season, he wears a white hoodie under his jacket. Because of his tendency to wear his uniform in such a manner and the fact that he seems to attract trouble, many people easily mistake him for a delinquent. On holidays and weekends, Touma generally wears a casual shirt and pants.
Touma is the type that acts before he thinks. He can never just sit around upon seeing someone in a pinch and will go to great lengths to protect or help the person. This he does at great risk to himself, which typically results in him being hospitalized for several days after each confrontation. When fighting seriously against a particularly strong opponent, Touma would usually first declare that he'll "destroy that illusion" of theirs, before actually engaging. He once answered to Himegami Aisa's question about the reason why he saves people: "I don't need a reason to save someone". It is evident that even when he is in a blank slate after losing his memories, Touma can still display such personality. Although lacking his memories, Touma does not appear to mope over the loss of them in particular, as the beliefs from his pre-blank state continue to motivate Touma onwards, allowing him to understand what he needs to do, even if he doesn't remember. However, after losing his memories, he now seems to approach people with more caution, carefully choosing what emotion or mood to display when meeting someone he thinks he might know, lest they see through his ruse and exploit him in any way. When Touma meets Stiyl once again after saving Index, he displayed politeness and casualness towards him which made Stiyl suspicious. Touma then realized his mistake quickly and created an explanation for his behavior. Touma also bears no grudge on former enemies, and is willing to help them if they asked for it
Touma's ability is the Imagine Breaker, a mysterious power that resides in his right hand that he has had since birth. It is able to negate all supernatural powers like magic, esper, and divine powers, a fact proven to be the reason for the fear of Archangel Gabriel not wanting to touch him, and is speculated by Index to negate the divine protection of God and his blessing, as well as the red string of fate. Born with it, Touma is the current holder of the Imagine Breaker, and the mysterious power itself has a preference to Touma being its bearer, as there is meaning in Touma having it in his right hand, or in Fiamma's own words: "the right hand is only the right hand when it is growing from his right shoulder." According to Othinus, Touma's knack for escaping dangerous situations through external factors and his inability to die is a form of misfortune as well, and refers to it as his "greatest of all [his] misfortunes".
Due to the fact that it is not an esper power, the people testing esper abilities cannot detect or properly classify, making him a Level 0 as he too has passed through the Power Curriculum Program. As such, Aleister Crowley considers him neither an esper nor a magician but rather a normal person with a unique ability. This gray area allows Touma to participate and get involved in the intrigue of the other side without causing a political backlash for technically being part of the Science Side.
There is a lot of unknowns regarding Touma’s power, and many are the speculations of the true extent and form of his power. Of this is Terra of the Left who has hinted that the Imagine Breaker might extend itself further away from its bearer's right hand, based on Terra's personal knowledge of Fiamma of the Right's Holy Right ability. As well as that of Ollerus, who has stated that the Imagine Breaker is the reference point of the world, bringing the world back to normal when it is distorted. Despite of the extents of Touma's abilities, Touma might not have the ability to negate all "artificial" supernatural abilities. Tsuchimikado Motoharu is convinced that there are things that Touma's Imagine Breaker cannot destroy, including ley lines or a person's life force from which a magician's mana is produced, as evidenced by the fact Touma hasn't killed someone through a simple handshake. This fact is corroborated by Leivinia Birdway, stating that although Imagine Breaker works exceedingly well when it is normalizing abnormal values, it does not show much power when dealing with something that is uniform from the start. Because of this, if a supernatural power/object is sufficiently powerful or massive enough in size it will not be completely negated right away as it will take a longer time to fully defeat, things such as Dragon's Breath, Innocentius, Accelerator's Black Wings, and others. To compensate for this glaring weakness, Touma realizes that he need not negate but simply cast it aside, disrupting it so to speak. It is during the state where he cannot negate it completely that Touma can physically touch or grab the power/object, negating and disrupting it instead of instantly destroying or completely ridding of it right away. This is exemplified during Touma's fight with Accelerator in Russia, Touma pulled one of Accelerator's black wings to throw Accelerator off balance and dodge the attack when Accelerator struck Touma with 100 wings that he summoned. That single touch was capable of negating the vector controlling power of said wing as well.
Touma is also a capable street fighter and quick thinker as shown in his fight with Aureolus Izzard where he exploited the weakness of his "Ars Magna". His fighting capability is stated many times in the novels to be the result of countless fights he was involved in with other delinquents when he tries to help other people, even when his opponents are Skill-Outs that carry deadly weapons. Also Touma has an incredible amount of stamina as displayed during Mikoto's attack on him where he took in every attack she threw and was still able to combat and beat Accelerator. He possesses a high threshold of pain, as demonstrated against his battle with Aureolus where his entire arm was cut-off and he was still able to think straight enough to beat Aureolus, although Stiyl said he just got "high" off of the pain. Touma is also very fast and has great reflexes that allow him react to attacks. Even while intoxicated, he could easily avoid Mikoto's lightning attack while walking away from her after World War 3.
In spite of the examples above, Touma still only sees his fighting capability as "capable of winning one-on-one, maybe possible of winning two-on-one, and run away when it is three-on-one".
During the British Halloween, Touma displays the ability to be able to sneak and hide from others very carefully. During volume 20, Fiamma was amazed at how well he has gotten at doing it while he was trying to fight and locate him during his current ventures in Russia.
Touma has also displayed an aptitude for fighting cleverly against more conventionally-armed foes. In volume seventeen, knowing that there is a gun-wielding terrorist waiting for him directly in the cargo hold of a passenger plane, he pours heated coffee and tea into a ventilation shaft which he uses against the terrorist, tricking him into firing on the shaft and dousing himself in boiling liquid, rendering his gun useless at the same time while Touma is able to directly confront and defeat him. By "New Testament" Touma has become quite capable of analyzing magic himself without the need for magicians. This is exemplified in his fight with Freyja where he discovers what her magic is based on without a single correction from Index. During the manhunt for him and Othinus, Touma further displays how far his analyzing skills and cleverness have come. While demonstrating a knowledge of underlining working magic styles from his past experiences and the fighting tactics of his opponents, as he could quickly find the weak point in his opponents' spells, fighting styles and personalities where he would use them to his advantage to force them to draw or defeat them.
- In the AWA fics, Touma is currently dating Mikoto Misaka after getting forced by everyone.
- According to the Toaru Kagaku no Railgun manga, because he has to cook for himself, he possesses great culinary skills.
- The novels point out that his zodiac sign is Aquarius.
- There is a sort of running gag in the show with Touma being fond of telling people that he'll "break their illusion", before proceeding to beat them with his right hand. More specifically, he says "I'll kill it... That illusion/fantasy of yours!!" It's actually a pun: The Kanji given for 'Imagine Breaker' is 'Illusion/Fantasy Killer (Gensou Goroshi)', hence this gag, most times Touma says this line, a particular music track can be heard, the track is named "Gensou Koroshi" also.
- Currently, the only Science Side characters who know Touma's involving in the incidents of the Magic Side are Aleister Crowley, Etzali, Tsuchimikado Motoharu, Kazakiri Hyouka, Accelerator and Hamazura Shiage.
- Almost every person Touma defeats throughout the whole series also ends up fighting alongside him later in the series.
- It is understood that he is a threat for a Kihara or at least for Kihara Byouri when Enshuu uses those patterns in relation to Touma.
- Ironically, despite having a preference for older women, most of the girls Touma attracts are considerably younger than him.