Kamijou Faction

The Kamijou Faction (上条勢力), or Kamijou Party, is a "new group" which technically does not exist in any tangible form. However, the possibility of the "faction" becoming a real group is "feared" by certain individuals on the magic side, including Etzali (initially) of the Return of the Winged One, because it might destroy the actual balance of power between the magic and science; the group "violates the regular rules" existent in current organizations since "it's composed" of espers, magicians and regular people who were allied with Kamijou Touma, contrary to most organizations that use only magicians, only espers or only people unrelated to either side in their operations.

Initially the group is mentioned by Etzali and after that, its name is never mentioned again by any other characters except Lessar and the High Priest, so the name can be considered non-canon, but the individuals' connection with Touma are canon.

Background
Excluding Index, Touma meets his allies unexpectedly, and they help each other in many situations. Their connection with Touma were formed due to many reasons such as they have feelings for him (Misaka Mikoto and Itsuwa), they are friends of him (Tsuchimikado Motoharu), they have respect for him (Stiyl Magnus and Kanzaki Kaori respect him for saving Index), their lives were saved by him (Himegami Aisa and Lessar), they were encouraged by him despite the fact that they were not human (Misaka 10032 and Kazakiri Hyouka), they changed their ways of living after being defeated by him (Accelerator and Hamazura Shiage), they have a history with him (Kumokawa Seria and Shokuhou Misaki), they wanted to use him for the Imagine Breaker (Leivinia Birdway), or they faced the same enemy when they met each other (Sogiita Gunha and Kakine Teitoku).

Etzali pointed out that the most troublesome thing about the group was that they took radical actions in order to solve problems and thus "couldn't be ignored". Etzali also pointed out that every member allies themselves to the group out of their own volition, beliefs and conviction, and thus they would never betray Touma, can't be bribed out of the group, and would not switch sides regardless of the consequences. He references on how the faction will survive even if Touma dies, as the bonds between the various members can't be dissolved.

Allies
The individuals below are not 'members' but rather people who were connected with Touma. Most of these people used to lead difficult lives or have problems that they could not handle, such as in Index's case, being a container of the 103,000 grimoires. Moreover, some of these people have been previously antagonistic towards Touma, such as Kanzaki Kaori. However, Touma helped them even if they refused his help, because of him, their lives were changed and they had become trustworthy allies who helped Touma in battle or other situations (except in his unlucky peaceful daily life and his homework). They are also grateful to Touma and believed in his strength. One of the evidence is confirmed, like his friend Tsuchimikado Motoharu who once warns Aleister that if he wants to use Touma for his unknown but selfish plans, Touma will break down Aleister's illusions.

Their relationships with each other in the story are normal (sometimes in a comedic way) when it is peaceful. But when a crisis occurs, they seriously helped each other so they can return to those peaceful days.

Individuals like Etzali, Sherry Cromwell, and Vento of the Front were never seen helping Touma, but they used to fight him and they were defeated by him. After that, they changed their ways of living and had their own reasons for providing support.

Abilities and Powers
One of the dangerous attributes of the so-called group is the diversity of the individuals involved with it. Most individuals possess unique powers and abilities that make them noteworthy or infamous in their respective sides.
 * Kamijou Touma possesses the Imagine Breaker which can nullify anything related to the supernatural, and has another mysterious power as shown when he fought against Fiamma of the Right.
 * Index possesses 103,000 grimoires memorized in her brain, making her a Magic God candidate and sought after by many magicians.
 * Misaka Mikoto possesses the Railgun ability, which makes her the Number 3 Level 5 esper in Academy City and the strongest Electromaster.
 * Kanzaki Kaori is a Saint, of which there are less than twenty in the world.
 * Tsuchimikado Motoharu is a Magician-Esper hybrid and the only successful one in the world.
 * Himegami Aisa is a Gemstone and possesses the ability "Deep Blood," which attracts and kills vampires.
 * Accelerator is the Number 1 and most powerful Level 5 esper in Academy City and he wields at least Angel-class powers when in his "Awakening" state.
 * Kazakiri Hyouka is an AIM being and the conscious form of the Imaginary Number District (Artificial Angel), who is at least an Angel-class being.
 * Last Order, clone of Misaka Mikoto and administrator of the Misaka Network, is used to summon AIM beings (Fuse=KAZAKIRI and Aiwass).
 * Hamazura Shiage is a Level 0 who defeated Mugino Shizuri, the Number 4 Level 5 in Academy City. He also has allies in Skill-Out and ITEM.
 * Kumokawa Seria, advisor of the member of the Academy City Board of Directors Kaizumi Tsugutoshi, she has enough skills at manipulating people to match the Level 5 ability Mental Out without a mental esper power.
 * Acqua of the Back, former Saint and member of the God's Right Seat with the power of the Divine Mother's Mercy, is a powerful veteran mercenary and magician.
 * Leivinia Birdway, the leader of the magic cabal Dawn-Colored Sunlight, is powerful enough to be compared to a Saint.
 * Kuroyoru Umidori is a Level 4 cyborg with the Bomber Lance ability and was once part of the Dark May Project.
 * Thor is the second strongest member of GREMLIN, able to fight equally with a Saint.
 * Fraulein Kreutune, an immortal being who possesses strange powers.
 * Shokuhou Misaki is the Number 5 Level 5 esper of Academy City and the strongest Telepathy user.
 * Kakine Teitoku (Beetle 05) is the actual Number 2 Level 5 esper of Academy City and a being made of Dark Matter.
 * Sogiita Gunha is the Number 7 Level 5 esper of Academy City and the strongest Gemstone with an ability that can't be understood.
 * Othinus is the former Magic God and leader of GREMLIN. Despite being miniaturized to 15cm, she still possesses great magical knowledge.

Influence
As seen mostly in Shinyaku To Aru Majutsu No Index Volume 10, the influence of the Kamijou faction, or mostly the influence of Kamijou Touma himself extended, affects many other organizations. And as noted by Levinia Birdway, Kamijou's influence could turn to greater good or destruction depending on how he managed it.

Kamijou Touma has direct or indirect influence over the following: Kamijou has never used his influence over any organization so far, only going as far as stopping the Allied Forces from their manhunt against Othinus. Also, as stated by Lessar, multiple individuals and factions have started making plans to use his influence for their own benefit.
 * The Government of the United States of America (extended from his relationship with Roberto Katze).
 * The largest magic cabal in England the Dawn-Colored Sunlight (extended from his relationship with Levinia Birdway).
 * The dark side of academy city (extended from his encounters and relationships with Kumokawa Seria, Tsuchimikado Motoharu, Oyafune Monaka, Kaizumi Tsugoshi, Accelerator and so on).
 * England's royalty (as shown in the end of New Testament Volume 10, extended after the events of the British Halloween).
 * Many other unnamed smaller cabals and organizations that could move out of fear from Kamijou Touma, as shown by Etzali and Kanou Shinka, Touma's influence has moved deep into the large organizations that the smaller ones fear him not knowing of his real personality.
 * Despite their many attempts to kill him, Touma's mended relationship with Kamisato Kakeru, enables him to gain their aid so long as him and Kamisato work towards the same goal.
 * The cornerstone of Aleister's Plan, whom Aleister would rather not harm, and a favorite of Aiwass.
 * Connected with Judgment, Anti-skill, and Useful Spider through Misaka Mikoto, Aiho Yomikawa, and the members of Useful Spider who helped him save Patricia, respectively

Index Arc
Touma meets Index, and later meets Stiyl and Kanzaki. Kanzaki revealed Index's continous memory loss to Touma. Touma revealed the 'truth' to Stiyl and Kanzaki and they combined their efforts to save Index. After that, Index, Stiyl and Kanzaki changed their opinions about Touma. Index learnt about Touma's memory destruction so she tried to help him remember and later confessed her feelings to him while held back her tears. However, Touma managed to fool her.

Deep Blood Arc
Touma and Index meets Himegami Aisa. Index managed to persuade Touma to keep Sphynx. Touma 'meets' Stiyl and learnt about Aureolus Izzard and Aisa's secret. Aureolus Izzard reveals his plan and his past which involved Index. Touma defeated Aureolus Izzard and rescued Aisa. In the end, Aisa started to develop feelings for Touma.

Sisters Arc
Touma meets Misaka 10032. Later, he come across Misaka 10031's corpse and meets the Sister Clones. Touma later found out Misaka's dark secret and managed to convince her not to fight Accelerator. Touma managed to stop Accelerator from killing Misaka 10032. The real Misaka later arrived to see the battle. Mikoto and the Sisters managed to help Touma in order to defeat Accelerator.

Angel Fall Arc
Touma and Index temporary leave Academy City and headed for the beach. The next day, Touma meets his father. However, Touma noticed everyone's appearance have changed except him. Touma later meets Misha Kreutzev who attempted to eliminate him but Kanzaki and Tsuchimikado made it in time to stop her. They explained to Touma about the Angel Fall and Tsuchimikado revealed that he was a member of Necessarius. The next day, Touma is looking for the culprit and came across his family photo. Knowing his father's appearance has not changed, Touma searched for him and soon confront him at the beach. However, he doesn't know anything about the Angel Fall. Misha soon appears but Kanzaki arrived in time and revealed Misha's true identity, Archangel Gabriel. While she faced Misha, Touma and his father reached and entered their house and Tsuchimikado suddenly appears. Tsuchimikado revealed the truth and knock out Touma and his father. Tsuchimikado completed his spell and destroyed Touma's parent's house. In the hospital, Tsuchimikado revealed his true nature and abilities to Touma. Finally, Touma gets to see his mother's true face.

Three Stories Arc
Etzali says that his superiors considered a threat to Kamijou Faction. The arc would mark the first time the name Kamijou Faction is mentioned.

World War III Arc
While they were in the military truck in Russia, Lessar says that she doesn´t accompany Kamijou to become part of the Kamijou Faction.

Hawaii Invasion Arc
Leivinia manipulates the science side part of the Kamijou Faction in order to draw the true members of GREMLIN out.

Ichihanaran Festival Arc
Touma demonstrate his power and influence over his alliance by having them complete the ingredients needed to stop Fräulein Kreutune from eating a human brain as well as stop GREMLIN and Ollerus' group from using her for their plans. Here, Hamazura Shiage trusts Touma's orders despite lacking information, allowing for Touma's goal to be achieved.

Meanwhile, the most obvious demonstration of Touma's influence itself is showing off to Leivinia Birdway, as she prepares to shoot him, on how he is not alone, which is then promptly followed by Misaka Mikoto and Thor using their powers to give Touma time enough to recover and fight Leivinia again, despite busy fighting powerful opponents themselves.

Trivia

 * There is evidence that, in the Magic Side, magicians and organizations believe that this faction is very dangerous and influential; while others want to join.
 * Etzali was one of the first to point out the danger that this group presents, but despite that, he ended up "allying" himself with the ideas faction.
 * After Lessar mentioned the 'Kamijou Faction', she said that she does not want to be a part of it. However, she did not abandon Touma and kept on assisting him during his journey to save Index. Her journey with Touma is solid evidence that she is one of Touma's allies.
 * Since Touma is somehow related to several influential people, one could say that the faction has several resources. For example: Third Princess Villian, Elizalina, President Roberto Katze, Oyafune Monaka, or Kaizumi Tsugutoshi.