Kaizumi Tsugutoshi (貝積継敏 Kaizumi Tsugutoshi?) is a minor character in the Toaru Majutsu no Index series. He is one of the twelve people on Academy City's Board of Directors. He is notable for using Kumokawa Seria as his "brain," giving him great insight into matters due to her intelligence.


He is described as an old man. Living a life of luxury, he apparently wears formal clothes that would have fit in more in an antique setting.[1]


He is a man in the lap of luxury who enjoys the finer things in life, like music, theater, antiques, and fine arts. He preferred to enjoy his limited free time to its fullest during his long lifetime. However, this is not a result of a belief in moderation. Rather this is a result of his belief that alcohol, tobacco, and other things that, he believed, dulled the senses would only diminish his enjoyment. The only time he does drink is when he is stressed, during the most unpleasant of times.[2]

He is described as a petit bourgeois, referencing to his conventionalism and conservatism, after he said to Seria that no one will accept her report of just leaving the Americans and Russians try and gather Gemstones.[3] He is also described by Seria as a noveau rich.[1]

Although he can be described as having several attributes that are common with Thomas Platinaburg, and has also dipped in the Dark side of Academy City, with Seria, he has done several things that can be deemed as "good," like bringing the Gemstones into Academy City and preventing the Agitate Halation Project. Indeed, he is the one who asked Seria for help concerning the Gemstones that are being targeted by the various organizations around the world, referring to them as children who just happen to have certain abilities instead of Gemstones.[1]


As all the members of the board of directors are rich,[1] Kaizumi is no exception. He is apparently married, having a wife and daughter. An aged character, he has several connections with people, such as a conductor and even someone involved with the CIA.

He uses Seria as her brain, who enjoys thinking for him, and also does his commands. According to Tsuchimikado Motoharu, Kaizumi apparently "tamed" Seria into becoming his brain, though it is unknown how he managed to do so.[4]


Toaru Majutsu no IndexEdit

Toaru Majutsu no Index Light Novel Volume SS2Edit

Main article: Toaru Majutsu no Index Light Novel Volume SS2
The Second Friday of JulyEdit

Kumokawa Seria is able to make contact with Kaizumi Tsugutoshi in her school's cafeteria, while there is no one else around. Starting their "dangerous" talk, Seria references the commotion outside regarding the Gemstones, to which Kaizumi confirms, though wonders where Seria gets her information, though Seria says that he should be thankful that his "brain" is that excellent. Kaizumi then asks her what are her thoughts about the whole situation, to which Seria says that they should leave it be as the people on the outside really can't do anything. Kaizumi asks Seria if she really thinks that there is an idiot that will accept such a report. Seria sighs, referring to him as a petit bourgeois, and says that if a member of the board of directors were to write that report, like him, he can simply suppress complaints of the report around him. Kaizumi complains however that bureaucracy isn't that easy, though she says that as bureaucratic positions go his is pretty important.[3]

Seria however acquiesces to Kaizumi's request as she begins eating in the cafeteria. Seria then mentions the list of Gemstones, and states that since it has been created a little late then America and Russia have noticed that Academy City is making it, ending up with them making the list of Gemstones on their own. She then warns that they might get in the way of their work. Kaizumi says that if she knew that then she shouldn't have suggested "leaving it be" just then. Seria tries to confirm if their problems are finding a way to eliminate the problem presented by Gemstones scattered around the world, and other organizations gathering and analyzing Gemstones and creating their own esper development program, to which Kaizumi does. Seria says that it isn't a problem that America and Russia are on the move, and mocks their failure in the Cold War, and assuredly says to Kaizumi that the two great powers will be unable to complete their research regardless of the amount of samples they gather as they don't even know what the data means. Kaizumi asks how she can be so sure. Seria gives Russia's research as an example, where they have a person activate their special power by fervently praying to Mary. Here, Seria tells him that the Russians can't distinguish between what is "miraculous" or what is not, and that they don't even know what kind of miraculous thing they are searching for. Basically saying that since the Americans and Russian don't even know what path they are going, they can never catch up to them. Still adamant to accept it, Kaizumi demands proof from Seria, to which she says that he has to prepare the proof himself. Seria references that despite the claims of a number of institutions developing esper powers, Gemstones, their supposed "sample", are rare. Essentially telling him that it is unlikely for anyone to gather up the few Gemstones scattered around the world.[3]

Kaizumi is still hesitant however, to which Seria says that it is the only option and says that he should bear with the extra paperwork as she is his "brain". After a short silence Kaizumi then asks what a Gemstone truly is, to which Seria points out that only someone influenced by Academy City would ask a question like that as he always assumed that espers can only be created in Academy City. Kaizumi uses the "diamonds" metaphor here, referring to Gemstones as having been created when the exact same circumstances found in the laboratory are recreated in the natural world. He cites the Gemstones of Academy City, Deep Blood and Imagine Breaker, but says that they don't seem like proper powers. He explains it as if their powers lie in a different direction than the straightforward powers in Academy City. Seria adds the 7th-ranked Level 5 esper to his list, and explains to him that Gemstones having strange powers is a characteristic of theirs. She says that though they aren't powerful and are just rare, that alone gives them value to Academy City. Finally, Seria advises Kaizumi one more time as his brain, saying that he shouldn't categorize the Imagine Breaker as a Gemstone. She says that she doesn't know the details but she says that he is much more interesting than they think. Remaining silent for a bit as he was surprised that Seria said that she "didn't know" something, Kaizumi says that Seria seems to be enjoying herself. Here, Seria replies that she does because thinking is part of her job.[3]

The Second Friday of OctoberEdit

Kaizumi Tsugutoshi invites Kumokawa Seria into his fancy home for a conference with a CIA agent on his home theater system. After complaining of his expensive taste, the conference starts with the CIA agent explaining to them that the recent spate of simultaneous targeting of Gemstones all over the world has nothing to do with the CIA. The CIA agent explains that even though the CIA started the Stargate Project in the past to create their own espers for military purposes, but says the recent incidents have nothing to do with them. He then advises them to look over the organizations that are involved and then they will see that he is telling the truth.[1]

Seria says that he is telling the truth, saying that the various academic organizations, scientific thought groups, sports engineering groups, and human trafficking organization that are involved seem to be uninvolved with the CIA and doubts that they are backing them. The CIA agent agrees, saying that just because they are well known doesn't mean they are behind every world conspiracy.[1]

However, Seria points out to the man that for all those organizations targeting Gemstones, there are two CIA spies, surprising the man. She tells him that they noticed the CIA creating a network of their own with the organizations without the organizations even known. She asks him why, saying she doubts the leader of their country approves of their method. The man starts talking, but Seria simply ends the connection.[1]

With that Kaizumi asks what she thinks. Once again, as Seria has stated before, even if they gather and tinker with the Gemstones they will just fail and that they can leave them alone. For the Stargate Project, she says that it is obtaining the information on the failures of those individual organizations courtesy of its spies there, saying that failures are the seeds of success. She says that if they refer to the data on countless failures to create an outline, they may be able to succeed. Kaizumi asks what the odds of them succeeding, to which Seria says 0% and that they need not worry.[1]

Seria explains that even if they fail, they won't know how to use all the data they gathered, putting them in a standstill. Regardless, as long as they don't know that they have failed they will continue to use up the Gemstones. Kaizumi is relieved but asks her what they should do now. Seria says to him that he is still naive. He tells that though the organizations will fail on their own, he doesn't like what they are doing to the Gemstones. He then stops referring to them as Gemstones and says that they are kids that happen to have a certain ability. Seria says she has already answered that question. She says that it with only around Gemstones in the world it would be faster to take care of the Gemstones themselves. She advises him to invite them to Academy City as it would be the most efficient method of protecting them from the various organizations. She tells him that his kindness forestalled him as despite thinking the Gemstones as kid who have lives of their own but in the end he did nothing. Kaizumi admits he was at fault as well, but now says that she is asking from him something impossible. Kaizumi says that the organizations are using the Gemstone list that CIA prepared via different routes than theirs to begin "mining" the children nearby. He tells her that if they dispatch forces they still won't make it in time to stop the "mining" taking place simultaneously across the world.[1]

Seria responds that thought it is true that they won't make it in time even with the help of the supersonic passenger planes, they still have cooperative institutions scattered around the world working with Academy City. Kaizumi reasons that the institutions are merely companies and that fewer than 10 of them have military capabilities, as such they would be unfit to lead the rescue of the children. Seria says that it may be true on the surface, but they still have a trick up their sleeve with them. She says that she doesn't like owing favors, but they should bow down to the Frog-faced Doctor for help. Kaizumi asks what she is talking about, to which Seria explains that she is going to have to rely on girls with identical faces to fight for them.[1]

Thus begins Academy City's operation to rescue Gemstones of the world.[5]


Main article: DRAGON Arc

Kaizumi is briefly mentioned by Tsuchimikado Motoharu when GROUP is on the run and in needing an ally on the Board of Directors to fight against Shiokishi. Here Motoharu rules out Kaizumi as an option, since Seria would not be fooled easily and might advise him against helping GROUP.[6]

Shinyaku Toaru Majutsu no IndexEdit

Homecoming ArcEdit

Main article: Homecoming Arc

After Kamijou Touma is revealed to be alive and have returned to the city, Kaizumi tries to get Seria back to her former self. It is revealed that during his absence from the city she became lethargic and commented on being regretful neither she nor the director Kaizumi could help out Touma despite the fact they had power. [7] After an attempt to re-energize herself, she commented she couldn't keep such appearance even for a conversation as it was hollow and she was not like Shokuhou Misaki to which Kaizumi replies she must if she ever wants to resume her connection with Touma implying they knew each other more than it seems at first. [7]

Agitate Halation ArcEdit

Main article: Agitate Halation Arc

Kaizumi Tsugutoshi is with Kumokawa Seria in School District 3 during the height of Motoharu's quest for vengeance against those who have "killed" his sister, Tsuchimikado Maika. Here, it is shown that they too have been investigating the Agitate Halation Project and the killing of Maika. Seria warns of Motoharu's impending advance towards them after being contacted by him that he is coming and he is serious. Although he predicted that he would come for them, he asks Seria what to do next. Seria states that no matter what they do, Motoharu will always go after them, as such, the only way to deal with him is to confront him head on, telling Kaizumi to remove all the normal guards, removing his hiding places.[8]

Kaizumi is in his office during the entire fight between Seria and Motoharu. He is later contacted by Seria after she presumed she defeated Motoharu, requesting to prepares the parts of hers that she separated in Micro Cosmos but later loses contact from her.[9] Knowing that he will be soon facing an unpleasant situation, he drinks alcohol. Suddenly, Motoharu bursts into the office behind him. Meeting each other's sights, Motoharu asks him if he is prepared, to which Kaizumi confirms. Motoharu states that his death will not be quick but protracted and painful, but Tsugotoshi states that he was prepared for such a thing the moment he sat on his chair. However, he warns him that he may not understand what's going on and that even though killing him will end his revenge, he will never reach satisfaction as he does not know the truth. Motoharu says that he doesn't care for the Agitate Halation Project anymore, and only revenge is in his mind on everyone who is behind it. Tsugotoshi asks that if that's true, then would his revenge not end when Motoharu dies. Tsugotoshi lays down his cards, he plainly states that it was Motoharu that has "killed" Maika after discovering a reprisal on his investigations were afoot. To protect her, Motoharu faked the death of his sister by using techniques of the Dark side of Academy City. Tsugotoshi points out that his revenge is nothing by a farce. Motoharu states that the mere fact that someone targeting her life made him reach pass his boiling, as is the reason for his rampage. The old man does not understand why he didn't do his revenge behind the scenes, but Motoharu replies that is because he "killed" her. Despite saving her and the possibility of her life getting back to normal, he still betrayed her by breaking the rules he had set-up for himself, and used the ways of the Dark side of Academy City. Tsuchimikado Motoharu has failed from saving Tsuchimikado Maika from getting involved in the Dark side of Academy City. That is the reason why he has been going into a irrational rampage unbecoming of his cold demeanor when it comes to the Dark side of Academy City.[2]

Hearing his explanation, Kaizumi warns that the Agitate Halation Project runs much deeper than he thinks, and things will grow much worse. Motoharu accuses the old man of being behind the project himself. Kaizumi doesn't convice him any further knowing that he will not listen to what he will say, and says to Motoharu that he will understood soon enough. Having enough of his ramblings, Motoharu prepares for the man's torture, silencing him with a single blow, and tied his arms and legs to the chair with wire. Still conscious, Kaizumi tells him that he has not the time to a disbelieving Motoharu, who believes that he no longer has any pawns and allies. Kaizumi points out that it has nothing to do with whose side anyone is on. Motoharu mocks him for saying that a totally unrelated hero will show up. However, he still continues saying that a hero will surely come, and that he will now learn what he has been involved in. Just then, the elevator to the office has arrived.[2]

Kaizumi states that he has no idea who will come for him, and that he or she may not be involved in the darkness at all. However, he tells him that he or she will surely be his enemy. Kaizumi then realizes that him being killed was not the call by for Motoharu and the person to defeat each other. It was set up that way since the beginning. Motoharu becomes confused, realizing that his clash with Seria and Kaizumi were nothing but a means to an end. Wanting some answers, Motoharu demands Tsugotoshi to tell him of his involvement with the Agitate Halation Project, to which he confirms to him that he is just like him, working to try and destroy the Agitate Halation Project. He says that his failure to stop it may be enough of a reason for him to being involved in Maika's "death". While Motoharu is confused, Kaizumi asks what Motoharu will do now, stating that if the both of them are defeated, no one will be able to stop the Agitate Halation Project. He suggests to him to flee, but Motoharu states that he has no choice, and that he will defeat the one who is behind those elevator doors as so he can continue his revenge. However, when the door opened, Motoharu's worst possible enemy has arrived, the possibility that he had feared the most, the arrival of Kamijou Touma.[2]

Kaizumi is bound throughout the brief fight between Touma and Motoharu. After Touma defeats Motoharu, he tries to call the ambulance, but Kaizumi stops him, saying that if he calls an ambulance for him, he will surely be killed. Kaizumi tells Touma that the one behind the Agitate Halation Project hoped to eliminate anyone who would interrupt the project by having them defeat each other, and they have been built into these plans. However, Kaizumi states that since they were alive means that the situation has already left their expectations, telling Touma that Motoharu will surely live. He points out to Touma that because of that, they have now have the opportunity to counterattack. Touma ponders on he is supposed to fight, and what led Motoharu to his current ends. Kaizumi tells Touma that if he truly considers himself as Tsuchimikado Motoharu's friend, then his top priority must be what he was trying to protect, Tsuchimikado Maika. He warns that all of Motoharu's actions were motivated to protect Maika, but warns that the ones behind the Agitate Halation project may have seen through Motoharu's ruse and may even reach Maika. He plainly tells Touma that someone needs to stop them. Touma believes that this is supposed to be Motoharu's job, but the old man's words convince him that he is out of the picture, though he does not take it kindly. Kaizumi asks what Touma will do. Touma gritted his teeth, and decides that he will protect Maika. He asks where she is, to which Kaizumi answers that she is not in her dorm, referencing on how Motoharu was thorough in hiding her. Hearing this, Touma is left no choice but to attack whoever was running the Agitate Halation project and stop them. He steals the documents on the project from Kaizumi and begins leaving. Kaizumi says that what matters to him is that Touma stops Agitate Halation, but advises to that he should save a life in the process. Touma says that he will but only her life, and states that the only one who can truly save Tsuchimikado Maika isn't him. Touma unties Kaizumi, but warns him that if he lets Motoharu die, he will become his enemy.[10] Kaizumi presumably followed Touma's orders and had Motoharu treated.

After the events of the arc, Seria goes out to meet Motoharu to "execute" him. After the deed was done, Kaizumi is contacted by Seria to confirm the "kill", he asks if she will recover the body, but states that someone else will pick it up for them, as because the both of them knowing each other may cause strange conspiracy theories if she did, like the execution was an act and that he is still alive. Hearing this, Kaizumi states that it would be best to let their enemies pick him up. With that, she ends her call.[11] It is unknown if Kaizumi is aware that Seria spared Motoharu's life by faking his execution.

Kamijou ArcEdit

Main article: Kamijou Arc

Kaizumi was present during the board meeting following the recovery of Academy City and reports of Aleister's death. Seeing the apparent greed and eagerness to exploit the opportunity, to the extent of being willing to start a war, he was observing the other members to determine the most dangerous threats, intending to preemptively eliminate them with his Use of Force unit, while also keeping every possibility in mind concerning the remaining unknowns. He considered the possibility that the key code list might not be held by one of the board members, which was then confirmed when Accelerator arrived and introduced himself to them as the new Board Chairman.[12]



  • (To Touma, from NT 7): "If you claim to be his friend, your top priority must be what he was trying to protect."


Academy City Board of Directors

Board Chairman
Aleister Crowley (Anime) Accelerator Novel GT Cropped
Aleister Crowley




Board Members
Thomas Platinaburg (Anime) OyafuneMonaka-AnimeProfile Template Placeholder other
Thomas Platinaburg Oyafune Monaka Kaizumi Tsugutoshi
Shiokishi without suit (Anime) Yakumi Nakimoto Rizou (Anime)
Shiokishi Yakumi Hisako Nakimoto Rizou
Template Placeholder other
Neoka Norito
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