Returning to school for the first time since the Level 6 Shift project, Touma and Index meet Kazakiri Hyouka; a physical female school student manifestation of all the esper AIM diffusion fields in Academy City.Having befriended the non-human being, Touma sets out to protect Hyouka from Sherry Cromwell; a magician affiliated with the Anglican Church that had been lured to Academy City by its founder, Aleister Crowley, to test out the strength of his Imaginary Number District–Five Elements Institutionnote .
Kazakiri Hyouka is the conscious form of the aggregation of the AIM Diffusion Fields of espers in Academy City, the Imaginary Number District. She became self-aware inside the Imaginary Number District, after Kamijou Touma was introduced into Academy City 10 years ago by his father. Self-aware due to Aleister Crowley concluding that it would be much easier for the Imaginary Number District to be controlled, where he could predict its actions, and even open negotiations with it or even use coercion.Before the start of the arc, Hyouka wandered around between the border of the Imaginary Number District and Academy City, wanting to get away from the latter as she do not want to bear influencing and changing the lives of the denizens there. Her wandering however, was not unnoticed, as several people from the Kirigaoka Girls' Academy, the school that she was somehow supposedly going to the moment she was created, and formed a research facility just to study her phantom-like existence, and ranked her as one of the highest amongst all of its student due to her queer existence, believing it to be some kind of esper power, something that caught the attention of Himegami Aisa.Despite introducing consciousness to the Imaginary Number District, it was still a very unstable and hard to control element in Aleister Crowley's plans, despite even knowing of a way to control it. Wanting to shorten plans 2082 to 3277 as well as strengthen Kazakiri Hyouka through introducing a certain amount of "impact" to her, Aleister Crowley lures Sherry Cromwell of the Anglican Church. A troubled woman, she is already suspicious of the magic and science sides coming together, due to a traumatic event she witnessed 20 years ago, where her friend, an esper, suffered the drawbacks of using magic, and was later killed by the Knights of England after the higher-ups of the Anglican Church realized that they were in contact with the science side. Aleister plays her like a flute, manipulating her through information regarding the Imagine Breaker and the Index Librorum Prohibitorum being together, and the Key to the mysterious Imaginary Number District. Believing that she could protect her own world, she sets out to Academy City to start a war with each other, but as the self-proclaimed woman who has "as many convictions are there are stars," she had great doubts and conflicting motivations, one of which was just wanting to make both magic and science side think they were going into war in order to isolate themselves from each other, up to wanting to stop.
Conscious of the AIM Diffusion FieldsBefore 7 AM, Kamijou Touma returns to Academy City after aiding Yamisaka Ouma in curing the curse that had befallen the girl he has fallen in love with. Ouma escorts Touma back into Academy City, and with a little trouble, breaks into the city, which did not go unnoticed by Academy City surveillance, causing problems for Judgment and Anti-Skill, as Sherry Cromwell broke in at another gate around the same time, not hiding the fact that she's from the Anglican Church. Throughout all this, Sherry injures 15 people and critically injuring three others in her way in, forcing Academy City's Automatic Alert System.Tsuchimikado Motoharu immediately notices this and goes to the Windowless Building himself to berate Aleister for his lackluster effort at preventing her from getting in. Aleister does not heed Motoharu's concerns, telling him that he is aware of the intruder and use this opportunity. Motoharu reminds him however, that Sherry Cromwell is of the Anglican Church, and despite the agreement Aleister made with Laura Stuart, because of the several differnent factions that the Anglican Church consists of, some people like Sherry would obviously appear, despite his best efforts to distort and manipulate information in order to stop such things from happening. Motoharu reminds Aleister that a magician should be the one that takes down a magician as to preserve the balance between magic and science, and offers to take down Sherry. Motoharu laments this, as he would have to have his identity as a spy become public.
Aleister however, says that there is no need for him to do anything. Motoharu says that if they are not careful they are truly going to cost conflict, however, Aleister reiterates his point. Motoharu then realizes that Aleister would once again use Kamijou Touma, the one who is at the center of Aleister's plans, to fight the magician and shorten his plans in controlling the Imaginary Number District–Five Elements Institution. Motoharu asks Aleister why he is going on about such a trivial thing, to which Aleister says that it is not trivial, for the Imaginary Number District is like a wild horse that can rip through the entire world, and it would be easier to tie it down. Motoharu is still worried of a conflict breaking out. However, Aleister tells him that it is job to work behind the scenes, and that if he works hard enough there would be no worry for anyone to lose their lives in the upcoming conflict, much to Motoharu's chagrin. For the rest of the arc, Motoharu is forced in the oddjob behind the scenes to manipulate information in order to avoid a major war to break out between the magic and science sides.Touma returns, tired and worn out, back to his home, however, he comes upon Index who was tied up by Ouma again with his rope binding spell after she made a fuss about not bringing her along. Index berates Touma for leaving her, but never mind that as she just wants to be free of her bonds, and tells Touma to simply use his right hand to dispel it. Touma is reluctant of course, as Index would obviously try to bite him again, but Index insists that she will do no such thing. However, after Touma dispels the rope binding spell, she immediately clamps down on him, and tells him that she was worried as he went out to fight magicians and left her at home, and despite his inexplicable power he is still an amateur when it comes to magic. Touma could only say sorry, having nothing to say.
After eating breakfast, Touma readies himself to go to school, and tells Index to stay at home. He tells Index that once he goes back they'll go out to hang out. However, after Touma leaves for school, Index realizes that Touma has not prepared lunch for her. Distressed with this, Index asks Tsuchimikado Maika regarding Touma's school.As Touma goes to school, he meets up with Misaka Mikoto. He comments on how she is energetic, to which Mikoto nervously replies on how he could talk to her so casually in regards to what happened yesterday when he ignored him. Touma recalls and asks Mikoto why he called her back then. Mikoto nervously replies, trying to deny him the reason, and says that it was nothing. Touma asks her if it is nothing, then why did he call her. Seeing that Touma is trying to pry, she changes to topic, which ends with Touma's listlessness. Touma says that a lot of things happened the other day, to which Mikoto asks if that fake date of their tired him so much. Touma replies however that it is because he did some other things, to which Mikoto immediately accuses him of doing it with other girls. Touma calls Mikoto out on how she is the only one who would do such an embarassing thing, to which Mikoto tries to explain her situation but Touma has quickly left. Using his knowledge from his remedial lessons, Touma navigate his way through his school, though he cannot shake the feeling of being a transfer student on their first day of school. In the parking lot of his school, Touma meets up with Tsukuyomi Komoe, noticing the notes in her hands, Touma asks if they are getting a quiz, to which Komoe denies. Komoe then states that a university friend of hers has asked her to read through papers concerning An Involuntary Movement or AIM, and discusses it with Touma in detail as he accompanies her to the school. After separating, Touma readies himself in faking being the same Kamijou Touma from before his memory loss, and later, much to his relief, manages to trick them and discover that his class is pretty carefree. Celebrating that since Touma forgot his homework, they, who have also forgotten their homework, will be home free from scolding as Komoe will be attracted to Touma's misfortune.Komoe returns for morning assembly, and states that before they go to the opening ceremony, she would like to introduce them a new girl transfer student. Touma begins to suspect who it is, from Misaka Mikoto lying about her age, an gender-bent Accelerator, to the remaining Sister clones. However, much to his surprise, Index with Sphynx, enters the room. Everyone in the class is surprised, and Touma can only respond blankly after Index notes that he is in class. However, she is later pushed away by Komoe, and enters Himegami Aisa, the true transfer student, much to Touma's relief. Komoe later gives Index enough money for a taxi ride back home as she returns back to class for the morning assembly.
With that, Index wanders around the empty halls of a certain high school hungry, and arrives at the cafeteria finding a coupon vending machine. Wanting to prove to herself that she can use machines, Index inserts the money into the machine, but fails to push a button, making the machine eat the money. Meanwhile, Kazakiri Hyouka wanders the school by the apparent machinations of Aleister Crowley, called out to Index as she was troubled with the vending machine, believing that she is just a normal student in Academy City and a transfer student in the school. Seeing as she has manifested into the real world, her first action is helping Index take her money back from the vending machine. Index asks her name, to which she says that she is Kazakiri Hyouka. The two start chatting, with Index complaining about Touma ignoring her. Hyouka points out that Index clothes stand out too much for her to stay at the school, to which Index points that Hyouka's unform stands out too, to which she says that she is a transfer student. As such, Hyouka suggests that the two of them could change into the school's P.E. outfits.
Meanwhile, Touma escapes from the throngs of people heading for the opening ceremony, and tries to search for Index. He later hear her giggling voice in a room, and angry, barges right in through, berating Index. He later sees that Index and Hyouka are not decent, and is predictably punished by Index for it. After calming down, Index introduces Touma to Hyouka, whom she refers to as a friend. Hyouka immediately acts timid around Touma, to which Index tells Touma not to scare her. She tells Hyouka not to be scared of Touma and gives her Sphynx for her to pet. Later, Touma asks Index why she is here, to which Index states Touma forgot about her lunch. Touma points out that they're only half-day today and its just plain common sense. Index immediately goes on a tirade of "common" magic rituals, like the position of the spellcaster next to the defensive magic circle for protection against the main spell. Suddenly, Komoe appears before Kamijou Touma, worried that he wasn't in the opening ceremony. She berates Touma for casually flirting while she was worried sick, and references his uncanny ability for attracting women as his form of AIM diffusion field. Touma, annoyed with this asks Hyouka for her input on this queer situation, but when they turn to look, she has already gone quickly from them like phantom.As Touma is forced to attend the opening ceremony as well as a lecture from Komoe, Index waits for him, with melancholy drawn upon her face. Hyouka reappears again to Index, apologizing for leaving because of all the hoopla that was going on. Hyouka starts chatting with Index, concerned as she looks depressed. Index relates on how Touma is angry with her and seem to not want to hear her side of the story, and that when she called out to him, he turned away, and wonders if Touma has began to hate her. Here, Hyouka makes a point that Touma does not hate Index, and that him being mad at Index is a sign that they are good friends, who don't hide their true feelings from each other. Touma later comes to them and tells Index that they should go out, and asks if Hyouka, who is frightened of him, if she likes to come, to which she accepts. As Touma goes to get some money, Himegami Aisa appears to Touma, disappointed at Touma for giving off a dull reaction to her becoming a transfer student. Leaving that aside, Aisa asks Touma if the girl he is with is called Kazakiri Hyouka, to which Touma confirms and says that she is a trasnfer student. She tells Touma that she should be the only transfer student, and says that back when she was still attending Kirigaoka Girls' Academy, that the name of Kazakiri Hyouka always came up at the top of the rankings of esper abilities in her school, but tells Touma that one one has actually seen her and what class or year she is in. She tells Touma that with a little investigation of hers, she figures out that her power is called Counter Stop and that she is the Key to understanding the Imaginary Number District, and that a special research facility was created just for her, but there are still unknowns regarding her identity. Touma is incredulous at this, to which Aisa responds that Touma should merely be careful. Before leaving, Touma asks Aisa if she would look to join him, and though Aisa becomes estatic at the thought, declines his invitation as Komoe gave her an errand.
Due to the alert system, Judgment members is takes a leave from work to help her search Anti-Skill for the intruders. One of this is Shirai Kuroko who is in charge in finding the other intruder, she notices Sherry Cromwell, her target, near the train station, apparently looking for something and has yet to harm any civilian since breaking in. Seeing the opportunity to apprehend her, Kuroko refuses to follow protocol. She uses a signal gun to warn the civilians that a battle is about to take place. Here, seeing the warning, the people in the station quickly leave, and Kuroko and Sherry are left alone. Kuroko tells Sherry not to move, but Sherry does not heed her words. Bothered by it, Sherry takes out her pastel chalk, but before she could cast a spell, Kuroko appears before her, surprising Sherry, as Kuroko teleports her to the ground, and shortly teleporting spikes unto her clothes, pinning her to the ground.However, despite being overwhelmed by Kuroko, Sherry has already written a magic code upon the ground she is pinned upon, and catches Kuroko unawares. A giant arm, made out of various solid objects, looms above Kuroko, who is unable to teleport away as she in pain, being caught in the ankle by the Sherry's golem's mouth. Kuroko doesn't know magic, and can only presume that Sherry is an esper from the outside. As the arm launches towards Kuroko, Misaka Mikoto arrives just in time to cut the golem's arm with her iron sand attack, severing it cleanly. Finally, as a finishing blow, Mikoto fires her Railgun towards the severed arm, blowing dust and smoke in their surroundings. Sherry uses this to her advantage, as she quickly escapes from Kuroko's spikes. Mikoto later calms Kuroko's nerves, and tells her to rely on her more. Much to her frustration, Kuroko takes advantage of the situation and starts molesting Mikoto.Alone, Sherry then begins her search for one of her targets. Using Automatic Writing, Sherry figures out the name of one of her targets, Kazakiri Hyouka, the Key to the Imaginary Number District. She then uses her magic to summon several mud eyes to search for the name that she has found.Touma, Index, and Hyouka visit the School District 7 Underground Shopping Center. Here, Touma suggests that they should go eat first, to which he asks Index and Hyouka. Hyouka however, becomes timid as Touma focuses his attention on her, remarking it's because he saw her naked, though Touma couldn't hear her. Index then chastizes Touma for his behavior around Hyouka, and as they argue, Hyouka is forced to choose a restaurant in order to end it. The restaurant she chose is School Lunch Restaurant, and after ordering their meals, Hyouka mentions that it is her first time eating this kind of cafeteria food.Meanwhile, back at a certain high school, Yomikawa Aiho of Anti-Skill, is making fun of Tsukuyomi Komoe, regarding Kamijou Touma's secret meeting with outsiders, and later asks Komoe to confirm if there were actually two outsiders, leaving Komoe confused. Aiho then receives a call for work as Sherry Cromwell has been found, and later leaves. Himegami Aisa then enters the room, carrying a book that Komoe asked for, whom stayed back as she was helping her friend finish her report on AIM diffusion fields. Komoe apologizes to Aisa for troubling her, and then tells her about on how Touma went off not with just Index but with another girl as well. After Komoe describes her, Aisa then asks Komoe if there really is a Kazakiri Hyouka in this school.
The three of them later go the Underground malls various arcades and amusement venues. Back at the school, Aisa tries to contact Touma's phone, but due to being underground the receptions is terrible, and Touma is unable to understand the caller. Back with Index and Hyouka, Index tells Hyouka not to be scared of Touma as he will not do anything bad to her, to which Hyouka says that she doesn't herself, and describes her feelings for Touma, as the hesitation one feels when one comes upon a wool sweater with a lots of static electricity, and assumes that it just because it is her first time talking to a guy. They later drink soda from a vending machine, to which Hyouka says that it is her first time. Index later forces Hyouka into a cosplay photobooth, and at the same time as Touma finishes his call. He comes upon the booth, and though Index and Hyouka warn Touma not to come close, Touma tempts fate, and much to his misfortune, their movement in the photobooth causes the curtains that cover the booth to fall. Touma is predictably punished by Index.
Index gives Hyouka half of the pictures they took together and comments on how school life is great, to which Touma disagrees, citing his reasons. Suddenly, a girl from Judgment confronts them and tells them that she has been trying to contact them through telepathy, and tries to send out a message to the three of them. Index and Hyouka receive the message, but Touma is unable to receive it. Failing this, the girl tells them that there is a terrorist in the underground mall, and that a red alert has been issued. The operation to detain her would start in 902 seconds with likely gunfire, and by that time, the separation wall in the underground mall will closed down, and sealing it to prevent the escape of the terrorist. As a Judgment member she is instructed to have everyone escape as soon as possible. She explains that she is using telepathy to prevent the terrorist from knowing of the operation. With that, the Judgment personnel leaves them. Touma heeds the instruction, and tells Index and Hyouka to go before the wall closes down. However, a voice calls out to them, and then the three of them are horrified to discover that a mud eyeball is stuck on the wall. It is Sherry Cromwell, who is apparently delighted that the Index Librorum Prohibitorum, Imagine Breaker, and the Key to the Imaginary Number District are gathered up in a single place, though saying that she'll just kill them all. Index upon seeing this, recognizes that it is a golem that has been forced into the role of an English guardian angel. Hearing this, Touma realizes that the terrorist maybe a magician. There, a large rumble reverberates throughout the underground mall, the separation wall closes down, and the lights disappear. The detainment of the terrorist has begun.As Anti-Skill battle Sherry Cromwell, Touma, Index, Hyouka, and a whole lot of civilians are stuck inside the underground mall, as the seperation was forcefully closed down. Seeing that he has no choice but to fight, Touma suggest to Index and Hyouka, that they should go and hide as he will take care of the magician himself. Index says that it is her job to face the magician, and tells Touma and Hyouka to hide. Touma and Index begin to argue, and ignores Hyouka's attempt to ask if she is of any use. Hearing footsteps around the corner, both Touma and Index tell each other to run away as they try to face the impending threat, however, both trip upon each other, and making Sphynx mew.
Meanwhile, Kuroko, whose duty it is to aid civilians to evacuate, is escorted by Mikoto (who spotted Touma in the guard room's surveillance camera and came rushing towards his location), both of which hear Sphynx's mew, as they turn around the corner, Kuroko and Mikoto, much to the latters surprise, see Touma and Index fallen down closely together on the floor. Mikoto demands Touma for an explanation on why he is there with a girl on top of him, but before he could respond, Index asks if Touma knows who the two classless women in front of them are. Kuroko is speechless, but Mikoto just becomes irate. However, the both of them suddenly discover the both of them has been saved by Touma without being asked, and the both of them then asks what he is doing behind the both of their backs. As the two of the lecture Touma, and he then explanation, Hyouka is unable to speak up and is frightened by Kuroko's expressions after hearing that Mikoto confided to someone like Touma.Seeing on how Touma is involved with something troublesome again, Mikoto asks if the terrorist is related to the goth woman Kuroko fought with. Kuroko briefs them on how she is troubled because of the fact that there are two seemingly different intruders today. Hearing this, Touma could not help but point out that he was the one who was likely the other intruder, and explains the reason, to which both Mikoto and Kuroko exasperatedly let him slide. Kuroko then tells them that it is her job to help the trapped civilians escape as she has the teleport ability. After much argument on who should leave the underground mall first, both Index and Mikoto got teleported by Kuroko, leaving Touma and Hyouka behind. Touma apologizes to Hyouka for leaving her behind, to which Hyouka replies that she doesn't mind. However, the battle continues to rumble on forwards deeper within the underground mall, Touma specifically tells Hyouka to stay and wait for Kuroko as he will try to stop the magician, quickly leaving her alone.
About 20 Anti-Skill personnel has engaged Sherry for a while, and Sherry and her Golem Ellis' movements continue to rock the Underground mall. Despite being on the offensive, the Anti-Skill is unable to pierce through Sherry Cromwell's Golem Ellis' defenses. One of them tries to use a grenade at it, but Sherry notices this, and uses her golem to make the Anti-Skill fumble. Immediately after, the grenade explodes, injuring the Anti-Skill, and the golem continues its rampage.Though there are no casualties, the Anti-Skill suffer terrible injuries, and by the time Touma finds them, they are still recovering their wounds. Touma is shocked that a magician could defeat the force of the science side, but presses onwards. Yomikawa Aiho who is part of the team, recognizes Touma as one of Komoe's students, and tries to stop him, but fails to do so. As Touma goes further into the darkened halls, Touma finds Sherry Cromwell and her golem. Sherry notices that he is the Imagine Breaker, and wonders where the Key to the Imaginary Number District is, but then says that it doesn't matter if the one she kills is him. She makes no effort to hide that she is from the Anglican Church, introducing herself from it to Touma, surprising him, as Index came from the same denomination. Here, Sherry declares that she wants war, and wants a reason for it, telling him that she wants as many people as possible to know. She orders Golem Ellis to attack, but to protect Touma, the still able-bodied Anti-Skill attack with their rifles, chipping away at it, but to no avail. While the hail of bullets fly, Touma hears footsteps behind him to discover Kazakiri Hyouka.
Touma demands to know why she is there, but Hyouka hesitates to answer, Touma then tells Hyouka to get away, however, as the battle goes on, a debris hits her square in the face, utterly obliterating a side of her head. Touma goes to her side, but discovers something queer. There is a strange rectangular prism-like object inside Hyouka's hollow head, controlling her movements. Here, Sherry too, is stunned and watches as Hyouka discovers what is inside her head. In her terror however, Hyouka runs towards the wrong direction, Touma tries to stop her but is too late. Sherry orders Golem Ellis to attack her, downing her through brute force. However, she somehow survives. Terrified, she runs away again. Interested, Sherry orders Ellis to follow her, and destroys surrounding walls as so Touma and the others will not interfere with her hunt, though just simply slowing down Touma and the Anti-Skill's advance.As Kuroko returns to find that Touma and Hyouka are gone, she is forced to prioritize to help the other civilians trapped in the mall as well. Meanwhile, as Touma helps the Anti-Skill clean up the debris and once again, is able to lose them with little effort, going towards where Hyouka and Sherry went. As Anti-Skill lick their wounds in the distance, Touma goes to a antennae area and contacts Tsukuyomi Komoe, to ask her about regarding Kazakiri Hyouka. Here, Komoe does not hide to Touma that she was looking for him and that Aisa tried to contact him a while ago but failed. Touma tells him about his position, and Komoe perfectly guesses that Touma is talking about Kazakiri Hyouka. Komoe shares her suspicion on how Hyouka was not caught in any of the surveillance entering the school premises, despite appearing before Touma and Index. Komoe explains to Touma about the AIM diffusion fields that espers emit again, and tells him that a phenomenon would occur, if energies that consists what humans are made out gather together, should form a human. With the 2.3 millions of espers in the city, with all their different powers, and in turn, differen AIM diffusion fields, it would create a process known as Kazakiri Hyouka.
Touma says that Hyouka doesn't seem to notice this as well, as if she always thought that she was normal human. Komoe asks if she thought she was human from the start, there should be no reason to suspect that she wasn't human. Komoe says plainly that Kazakiri Hyouka is not human but a physical phenomenon created by AIM diffusion fields. Touma is shocked after hearing this, interacting with a phenomenon, to which Komoe replies to him with a lecture. Komoe says that, indeed, Hyouka is not a human, even if she has everything that one could deem a human, despite this, she is still not human, a nature that is non-existent, an illusion that will disappear on the slightest touch. She then asked Touma what he thought of Hyouka in his own eyes, if she was just a lifeless illusion to him. Touma tells her that even if she was just an illusion, that doesn't mean she should disappear. Hearing his reply, Komoe is glad on how Touma was brought up the right way. With that, Touma decides he will try to save his important friend.However, Touma has one debacle: the golem. Surely, he cannot handle the golem himself in the narrow halls of the mall, where every movement of the golem cause the surroundings to tremble. Touma debates with himself for a while, then discovers that there are Anti-Skills he had left behind. Touma later goes to their side and simply asks them to help his friend, and there, they formulate a plan to save Hyouka and defeat the golem.Despite the massive injuries her body incurred, Hyouka is fine, and somehow, her body is able to regenerate, even her glasses. Suddenly, Sherry catches up to her, and immediately attacks her with Golem Ellis. Hyouka tries to escape, but is too late, the golem catches her hair, and drags her head down and grinds her body to the floor. However, even this, is quickly regenerated by Hyouka. Sherry is surprised that the Key to the Imaginary Number District is in the form of a timid girl. Hyouka asks Sherry why she is doing such a cruel thing, to which she says that there is no particular reason, that it needs to be her, but killing her is the quickest way. Seeing Hyouka's expression, Sherry tells her that she is not human, and demonstrates it by having her golem destroy a part of itself and then regenerate, just like what happened with Hyouka. She concludes that she and Ellis are the same, monsters. As Hyouka falls into despair and cries, Sherry tells her that she shouldn't cry, as it is unseemly for a monster like her to cry, and orders Ellis to attack Hyouka.
However, as Hyouka flinches, she discovers that she has been saved by the timely arrival of Touma, who used his right hand to stop the golem in its tracks. With the golem destroyed, Sherry quickly draws up a new one, and comments on how Hyouka should celebrate on how there is at least one idiot in the world who would protect her. However, Touma says to her that he is not alone, and much to Sherry's surprise, the Anti-Skills she defeated appear before her, rifles drawn and flashlights set upon her. Sherry commands Ellis to attack, however, the Anti-Skill go into formation, protect Touma and Hyouka, and start firing at the golem. it chips it slowly but is unable to move forward through the onslaught. Sherry commands the golem to force itself through, as such, it begins to move, and slowly gets used to the barrage of bullets. While protecting Hyouka and Touma, Yomikawa Aiho asks Touma if he is going to continue with his plan, telling him that nobody will blame him if he chickens out. Hyouka asks what he is going to do, to which he says it is to stop the golem. Hyouka pleads to Touma not to do it as he'd never make it, Hyouka tries to reach out to him, but Touma tells her not to touch him, as his right hand will surely destroy her too. However, Touma tells her that just because cannot touch each other, doesn't meant that they could not be friends. Touma tells her that he will be back, and that they could hang out with Index again.Sherry however, notices that the Anti-Skill and Touma are planning to do something, and waves her pastel chalk frantically to give the golem's steps more focus. The Anti-Skill then cease their firing in order to let Touma through. The unstable Ellis is orderd by Sherry to attack, to which it does so, attacking the ground Touma is in, delaying his progress. It raises its fist again, and Touma bends down towards the opening between the golem's legs as it tries to maintain its balance. With that, the Anti-Skill resume firing, and Touma confront Sherry. She can't move Ellis as she will only get his by the bullets, and seeing Touma, notes on how they are both trapped by the hail of gunfire by the Anti-Skill, but Touma says he doesn't need to, and just needs for her to sleep quietly, punching her in the face, and negates Sherry's control of the golem.
Touma tries to negate the golem, but then notices Sherry drawing a magic circle on the ground, making Touma believe that she's making another one. Sherry tells Touma that she cannot create and sustain two at the same time, and says that even if she tried, it will collapse like mud. However, she says that if she uses that principle, she can create a useful effect. With that, the ground under Sherry collapses, and she escapes, creating another golem, and destroying the one above.Despite escaping, Touma is still restless about Sherry, and recalls on how her interest with Hyouka were not very high, and then remembers on how she said that the one she has to kill didn't need to be him. Here, Touma realizes that her next target is Index.
While a now injured Sherry has formed a new golem, intending to find Index, Touma, Hyouka, and the Anti-Skill is stuck with each other. Touma demands to know why the separation wall has not been lifted, to which Yomikawa Aiho replies that it is not within their control. Frustrated, Touma goes to the hole that Sherry created, wishing that he can go down and chase her. Hyouka then asks what's going on, and Touma tells her that Sherry's new target is Index.Hyouka tells Touma that they should ask Anti-Skill for help, to which Touma says that Index will only get in trouble as she isn't part Academy City. Touma laments on how he is unable to get to Index, or get down to where Sherry is. Hyouka then asks if Touma is really going, to which Touma confirms. Hyouka however, says that it is all right as there is a way to save her without him doing anything, and shows that she herself will save Index, a monster must face a monster after all. Hyouka says that she may not be able to stop the golem, but says that she will use herself as bait for Index to escape. Touma is obviously not fine with this, and calls her out on still saying that she is a monster. Hyouka says that she is fine with being a monster, because it will be the key to saving Index. Despite Touma's remonstrations, Hyouka willingly falls into the hole, and Touma is unable to stop her. Hyouka lands violently onto the hard ground, but her queer powers allow her to easily recover. She quickly sprint towards the golem, determined to save her first friend. Here, she finally recalls that she is not of this world, and of the City of Shimmers, where she was the core of the whole machinery of the city, and her actions and thoughts influenced the people there. She also recalls that she saw Academy City at the edge of that City of Shimmers and longed to escape the burden of influencing that queer city. One day, as she walks upon Academy City, she notices Index being troubled, and reached out to help her, and there, she somehow manifested into the world, not knowing who she truly was, but mattered not as she has made her first friend, even if she hated her for being a monster.
Meanwhile, after being teleported by Kuroko, both Index and Mikoto wait for the others. After conversing about her destroyed Walking Church, on how Index is worried of Touma being with Hyouka, and on how Index believes Touma will always come back no matter how many times he goes off, Index leaves Mikoto as she is forced to chase after Sphynx, who has detected something queer. Mikoto stays behind as her powers will only stay away animals like cats. Here, she notices that the ground is rumbling for some reason. At the same time as this, Sherry has let Golem Ellis go before her, controlling the thing remotely. She also lets Hyouka pass her by, and later sets up a trap for Touma, seeing him as the person she needs to defeat.
Touma comes down the hole with a firehose he found lying around. After running deep underground for awhile, Sherry notices him and uses her magic to make a pillar collapse next to him. Sherry tells Touma that she has let Ellis go first and taunts him that it might've already found its target. Sherry continues to taunt Touma, telling him to be her opponent, as so he won't be able to save Index. Touma asks Sherry why she is causing a rift between the balance of magic and science. Sherry answers, and talks about on how espers self-destruct when using magic. She tells Touma of the tragic fate of her friend, Ellis, the first attempt at a successful Magician-Esper hybrid. With this, Sherry says that the magicians in their magic side, and the scientists in their science side cannot co-exist together, and that if they do not set up clear boundaries between each other, tragedies such as what happened to Ellis twenty years ago will happen again. Touma is confused on how contradictory she is being, but then realizes that Sherry doesn't want them to start a war between each other, but only have them assume that they are in a brink of war. This angers Sherry and summons several magic circles on the walls and ceilings of the underground tunnel, an ambush. As the tunnel begins to collapse however, Touma notices the magic circle near Sherry on the floor. Discovering that it is the one made to protect her, Touma charges towards it and negates it, forcing Sherry to stop the spell. However, as she was distracted, Touma is able to punch her in the face.
Sherry is down, but not out. She stands up again and continues to mumble on how she needs to create a spark for war, saying of her reasons, such as Academy City's security getting lax, the Anglican Church having the Index Librorum Prohibitorum go out of their hands, etc. Touma asks her what Hyouka and Index did to warrant her attack, asking her why she is causing conflict even though she doesn't want it. Sherry goes loose, telling Touma that she doesn't know. She says that she hates everything, wants to kill everyone who killed Ellis, and bury all the scientists and magicians together. However, strangely, she also says that she doesn't want magicians and espers top fight each other, and tells Touma that her mind has been in conflict from the very beginning. She tells Touma that to her, everything seems logical, and that's why she is in pain. She doesn't live for a single belief, but of many, and tells him that she has as many convictions as there are stars. Touma, upon hearing this, tells her that even though her words are contradictory, there was only one belief that sprouted all of her other beliefs, which is that she didn't want to lose her dear friend. Touma asks her if she saw with her own eyes that he and Index were unhappy together, and tells her that there is not a need for them to separate, as they are happy together. Touma then asks her not to take away his dear friend as well.Sherry completely breaks down, knowing that her wish can no longer be fulfilled, and that what she is doing is useless folly. She calls upon her magic name, and charges towards Touma with her pastel chalk. Here, Touma realizes that another belief of Sherry's, and that is she wanted someone to stop her. And with that, Touma destroys Sherry's pastel, and punches her face, destroying her illusion. Touma tie Sherry down with found materials, and continues on his way. However, Sherry quickly regains consciousness, and wonders why she isn't dead. She wonders what belief out of many will pop out of her. She understands Touma's pleas, but a contradictory thought forms out of her. As she moves, another pastel chalk falls out of her, and in her many convictions, gives out a meaningless order, to either destroy the target or abort the mission.
Index finally catches up to Sphynx, however, the cat begins to act erratically, and almost immediately, the ground begins to shake. The ground tears apart, and a large arm appears and attacks Index, who manages to escape. It is Golem Ellis, which is what Sherry Cromwell is controlling remotely, however, instead of running away, Index stands her ground firm. She narrows her eyes, and with the knoweldge of a 103,000 grimoires, analyzes the golem. The golem is based from the Kabbalah; its main use is for defense and the elimination of enemies. The golem was apparently created from the mixing of Anglican Church's spells creating a new spell, with the linguistic system changed from Hebrew to English. Index's discovers that it is also being manipulated from a distance. The golem tries to attack Index, but she shows no fear as she knows of ways of defeating it without magic—Spell Intercept. By reciting codes, Index is able to hijack the magician's commands. It works, all movements of the golem are intercepted by Index, and are given new movements that are completely destructive to it. The golem attacks again, and Index uses a long code that manages to make it fall, and buy her enough time. Knowing that evading won't be enough, she takes out the pins that holds her clothes together to take advantage of the golem's regenerative powers. Knowing that the regenaration of the golem occurs every three seconds after being severe damage, Index prepares her pin, which is like a spanner in the works. In a whirlwind of power, the golem stands up again and attacks Index, who dodges it and prepares her attack. She throws the pin at the golem, which absorbs it. The effect hinders it considerably, unable to come closer to Index. Smiling, Index prepares for another pin. However, the golem surprises her, blowing her away. She tries to use Spell Intercept again, but is interrupted by the golem's assault. Down on the ground, the golem prepares for another attack. Index tries to use Spell Intercept again, and is successful in saying a code but is no longer working. The golem slowly rips out the affected leg that Index used a pin on, and moves closer to Index. She realizes that the long distance manipulation has been switched to automaton mode, rendering her unique ability useless. Index looks up to her doom, as the golem roars fill the air. With tears in her eyes, Index whispers the name Touma before a sickening sound is heard.
However, like Touma before, Hyouka is now the one protecting Index, kicking the golem down with great power, much to Index's surprise. She discovers that Hyouka is injured after her attack, but then sees her powerful regenerative ability. Hyouka tells Index to run away, as the golem's regeneration goes haywire, making it bigger. Index tells Hyouka to run, but tells Index that she should do so instead, as she needs to fight the monster before them. Index says that she can't fight a monster like that, and that she'd die for sure. However, Hyouka says that it is all right, as she isn't human either, and apologizes to Index for it. With that, the golem attacks, and Hyouka manages to block with it her powers, but her form starts breaking apart. Suddenly, the golem attacks with the use of it's other arm. Hyouka flinches, but then Touma shouts towards her. He charges forward with his raised fist, and collides it with the golem. The moment it touches Touma's right hand, all it's power and momentum completely vanishes, and the golem collapses unto itself. Hyouka smiles, as if relieved, now with her nice illusion is over.
Index is later taken away by Kuroko and Mikoto, saying that Judgment and Anti-Skill are coming, leaving Touma to fend on his own as his Imagine Breaker will prevent Kuroko's powers. As Index struggles from afar to get away from them, Touma comes upon an abandoned building. Here, Touma finds a lone Hyouka crying, and as she turns towards him, she says that she was happy that she use all of her strength to protect her important friends. Touma doesn't reply, but lets her continue with her pour her heart out. She talks to Touma about how she has known from the very beginning what happens when a monster's true nature is revealed. She tells him that she could not do anything about being a monster, but since a person who called her a friend was in danger, she needed to save her. She comes towards Touma and leans her body into his, whom cannot even embrace her. She asks Touma why she must lose the thing that she holds dear, why she must be afraid, despite the fact that she just wanted her friend safe from her, all the while burying her face in the comfort and warmth of that boy's chest.
Hyouka continues leaning on him, justifyin her actions, that she wanted to be with her friend forever, and knew that she could become good friends with her. Then she says that it was impossible, she could not just stand by and allow her to get killed, at the cost of Index not hating or not being afraid of her. She keeps on crying, and trying to justify what she has done was a necessity, in spite of the fact that now Index may hate or even be afraid of her. Touma was silent for the entire time during Hyouka's self-depacration and justification, however, he finally speaks. He tells her that if she is in pain or is sad, then she is not a monster. He tells her that she is indeed human, and that her illusion isn't over yet. They turn around and see Index, looking for them, and as she sees them, tears well up in her eyes. Hyouka is unbelieving of this, as Index tries to approach them, pouting but teary-eyed. Perhaps not learning her lesson, Hyouka is still unbelieving of the fact that Index is looking at her like a friend. Touma tells that maybe indeed her composition is a bit different from humans, and that she may be able to do thing other people can't, but that doesn't change the fact that she is Index's friend. And at that moment, Index jumps into Hyouka's arms, like true friends.
Touma goes back to A Certain Hospital, bragging to the Heaven Canceller about on how he has improved and that there is not a scratch on him this time. However, he is quickly punished by Himegami Aisa and Tsukuyomi Komoe about her actions towards girls, like Kazakiri Hyouka, as well as Touma being in the custody of Anti-Skill. The doctor then tells him that due to Touma's recent actions, his hand would've gotten fractures, which stops Touma's bragging. Komoe then says that there has been suspicious events during this whole debacle. She says that there were great coincidences, like Kazakiri Hyouka specifically appearing before Touma, as well as the true nature of Kazakiri Hyouka being the Key to the Imaginary Number District, and finally, on how the terrorist was able to find Hyouka, despite she appearing just now, and implicates the administrators of Academy City. Finally, Komoe says that there were too many coincidences happenign at the same time, the most suspicious point of all. Only the Heaven Canceller can understand what's going on, as he looks towards the Windowless Building.
While in the waiting room, Hyouka begins to dissipate, saying that she has little time left in the world, as she is an existence of concentrated espers, as such, she can only exist in an unstable state. Index asks if it's because of Touma's power, to which Hyouka explains that it is not Touma's power because it if it was, she should've been destroyed long ago as she is an aggregation of all esper's powers, surpising Index as it is not in any of her 103,000 grimoires. Hyouka tells that it is time for her to go, and says to Index that will always be with her even if she doesn't see her. Index says that if they would ever meet again, to which she says that they will, finally parting ways.Back in the Windowless Building, Tsuchimakado Motoharu asks him if he is happy now that he is now closer to holding the key that can control the Imaginary Number District. He tells the man that he is a monster, an ironic comparison throughout the events that just have happened. To gives the Imaginary Number District consciousness and allow it to materialize into something like "that", adds to back-up his claim, and Motoharu claims him to be insane. Aleister says that it is easier to control humans, as they can be used through coercion and negotiation. Motoharu asks what would happen if he created a villain, to which Aleister replies that villains are much easier to control. The difference between these two is only in the method used one handle them. Motoharu then asks if there is any meaning to doing all this just to get the Imaginary Number District, warning him of the magic side not being easy after what happened with Sherry. However, Aleister says that if he had managed to attain the Imaginary Number District, there would be no need to fear magicians.
As Motoharu ponders his words, he discovers a part of what Aleister is thinking, and demands to know if he is making an Artificial Heaven. Motoharu warns Aleister that if the Anglican Church discovers this they will surely declare war, pitying Sherry for being manipulated because she only thought that she was protecting her own world. Aleister tells Motoharu not to be paranoid, as he does not intend to fight the Church, and tells him that these terms such as heaven is beyond him as it is the business of the magic side. However, Motoharu points out as if he was insulted, that nobody knows more about magic than anyone else except him, Aleister Crowley, the magician.Before leaving, Motoharu gives Aleister advice, and asks him if he knows something about the term hard luck, and tells him that it means that no matter how many times one meets a hellish fate, the person is lucky enough to overcome it safely. Motoharu tells him that he has no idea what he is planning, but warns him that if he continues using the Imagine Breaker, then he should ready himself not to treat him half-heartedly, for surely, his right hand will eat his illusions alive. As Motoharu leaves him alone in that Windowless Building, Aleister tells that all his illusions were destroyed a long time ago.With the appearance of Kazakiri Hyouka, Aleister sets his plan in motion in creating Fuse=KAZAKIRI, a prototype model, in order for Aiwass to be able to take form in the world. Meanwhile, with Aleister's actions, Motoharu is forced to act behind the lines, to manipulate information in order for him to stop war between the magic and science sides, a job that he would eventually fail at doing. Furthermore, despite the thousands of damages done during Sherry's attack, the Underground Shopping Center's repair has been hastened due to the Daihaseisai, removing all signs of damage from September the 1st.Finally, even after what Sherry has done, due to her combat and decoding capabilities, the Archbishop Laura Stuart, after intense negotiations with Aleister, gave her a generous disposition. She is punished with shutting her in and letting her do document arrangements to reflect on her actions. She would later calm down considerably, and would later try to move on from her past, and hope that she won't lose control again.
- A Day in the Limelight: For Index and Hyouka
- Arc Villain: Sherry Cromwell
- Bottomless Magazines: While the Anti-Skills are shown reloading a few times, they fire a lot more bullets than their guns can hold.
- Chekhov's Classroom: What Index said about secondary spells came in handy for Touma.
- Clingy Jealous Girl: Index and Mikoto, the two most important girls in Touma's life, finally meet. It's not pretty. Kuroko also does not like Touma because of Mikoto's interest in him.
- Golem: Sherry's creation Ellis.
- Ignorant of Their Own Ignorance/Locked Out of the Loop: This arc fully demonstrates that pretty much nobody in Academy City is aware of the Magic Side, to the point that they assume Sherry must be an esper after seeing her powers.
- Marshmallow Hell: Hyouka inflicts this on Sphynx without noticing.
- Shout-Out: Komoe jokingly imitates the iconic scene from Dragon Ball Z where Vegeta yells, "It's over 9,000!" (though she says 70,000 instead) while talking about if someone could detect AIM.
- Skewed Priorities: Index and Mikoto think their love lives are more important than a terrorist attack.
- Tomato in the Mirror: Hyouka didn't know she wasn't human.
- The Unreveal: Komoe won't explain how she can drive.
- Unwitting Pawn: Aleister claims every heroic act Touma does plays into his hands. He's also been keeping tabs on him since he was a small child.
- We Have Become Complacent: Sherry claims this about both the Science and Magic Sides.
- What Measure Is a Non-Human?: Even though Hyouka is clearly a sentient being, Sherry dismisses her as a creature similar to her golem. Hyouka even starts to believe it. Fortunately, Touma and Index don't feel the same way.
- Your Size May Vary: Mikoto and Kuroko are the same height in a few scenes, when Kuroko is normally a head shorter than her.