|Spoiler Alert: This page contains spoilers. Read at your own risk.|
|“||I lost all of what you could call feelings of love. They weren't sealed, so they can't be released. They weren't broken, so they can't be fixed. That which is lost, cannot be recovered.||”|
—Tatsuya, Volume 5, Summer Break
Shiba Tatsuya (司波 達也) is the main protagonist of The Irregular in Magic High School. He enrolled at the National Magic University Affiliated First High School in April 2095 with his younger sister, Miyuki (深雪). He was accepted as one of the students to be placed in the Course 2 curriculum, marking the start of the series events. In his second year, he transferred into the newly-created Magic Engineering Course.
Appearance and Personality
Tatsuya is a stalwart self-assured young man in the prime of his teenage years, who lives alone with his younger sister in Tokyo, under the directive of the Yotsuba Clan. Besides being their home's caretaker, Tatsuya's raison d'être is to be Miyuki's, his sister's, guardian. In that sense, one would regard it as rather appropriate and even convenient that the man designated as a sort of a bodyguard of the future head of one of the world's most influential magical organizations to have such a stern countenance and hard-bitten demeanor as himself.
Tatsuya possesses an athletic and sturdy body which measures 175cm tall (5'9") when he first arrives at First High School, which later on further develops to 180cm tall (5'11"). Furthermore, aside his deep-set eyes and piercing gaze, his looks are often considered rather plain. Other characters generally view him as austere and competent-looking.
His usual unyielding stoic countenance hardly ever betrays bewilderment or enthusiasm, but whenever it does, it's often at the minimum level. In the anime, he has dark black hair that reaches his clear blue eyes (it is inferred in the light novel that the color of his eyes are actually dark blue, similar to his sister's) in several unevenly-cut bangs. Except for the color of his eyes, Tatsuya's looks are altogether divergent from his sister's, a far cry from her magnificent beauty, as acknowledged by numerous people throughout the series.
|“||If they are siblings... Then they are siblings who don't resemble each other at all. On one hand, anyone who sets eyes on the younger sister will no doubt be captivated by her; ten out of ten people, or even a hundred out of hundred people, will agree that she is a lovely, beautiful girl. On the other hand, for the elder brother, other than his erect posture and piercing eyes, nothing in his ordinary appearance could be said to be attention-grabbing.||”|
Tatsuya is extremely intelligent and analytical. His emotions are merely skewed in a certain direction, with one particular aspect becoming especially sensitive. Thanks to his distinctive analytical power, he is able to promptly categorize people into hostile and non-hostile. (Normal people see 3 types, hostile, neutral and friendly, but they have a hard time quickly determining who is a friend and who is an enemy, since they aren't bestowed with such a peculiar sensitivity). This is certainly convenient for military and political reasons, which encompass most of his activities.
|“||To hunger, but not glutton. To arouse, but not lust. To tire, but not sloth.||”|
—A Narrated Description for Tatsuya, Volume 3, Chapter 2
As a result of extremely high-end custom magical procedures that he was unwillingly subjected to at a tender age, Tatsuya does not possess the ability to feel any strong emotions like fear, despair, envy, hatred, disgust, gluttony, lust, sloth, and love, with the exception of a single individual.
|“||To Tatsuya, for whom not even his own death could induce ‘true fear’ — more accurately, he had been deprived of such an emotion — the fear of losing Miyuki was all the more amplified for there being no other fears to temper him and shake him strongly, deeply, and utterly.||”|
—A Narrated Description for Tatsuya, Volume 8, Chapter 16
Due to the achieved results of the magical procedures, added to the extensively dire experiences amassed throughout his training years as a living weapon, one could state that the only remaining soft spot in his personality would be the love he nurtures for his younger sister. Because of this, he tends to either spoil her too much, or be extremely overprotective and completely ruthless when there are even the slightest threats towards Miyuki's safety. His world revolves around Miyuki and he loves her dearly. Moreover, in the eyes of people in general, because Tatsuya sees no problem with his recurring and rather blatant displays of affection towards his sister — although she also acts the same — , he is time and again labeled as a siscon [Notes 1].
Contrary to popular and widespread belief (mainly for the ones who have only watched the anime), Tatsuya is not apathetic to the point of deserving the emotionless label, since he can be kind and caring towards his friends, and even tease them for his own amusement. Furthermore, while he doesn't possess strong sexual cravings, he can still be feel aroused and indulge in carnal delight, as he is perfectly aware of the enticing beauties surrounding him, which also includes even his sister, throughout the series.
Due to being treated as a counterfeit Magician, he seemingly underestimates the merits of his own Magic abilities and constantly looks down on himself, although that is likely an act, since this consensus is the underdeveloped product of third parties' short-sighted perspectives. Additionally, it is left unclear if Tatsuya actually believes such a biased judgment. Nonetheless, one could interpret it so, since Tatsuya has a habit of exhibiting overabundant amounts of modesty, whenever he is praised for his outstanding dexterity and achievements.
Among his several idiosyncrasies, Tatsuya is often teased by his friends for displaying a total lack of common sense regarding social interactions, as a product of his numerous misunderstandings and uncanny responses towards regular teenage affairs, which could be explained by his deprivation of any real social background that did not concern bureaucratic matters.
In conclusion, Tatsuya is a man who, despite having undergone dire straits and having lost even his emotional freedom, is still confident in himself and his aptitude to change the world for the better, as proven in a number of instances throughout the series, for the good people he believes in, and for the actualization of an exuberant future for his beloved sister to rejoice.
Tatsuya is the eldest son of Shiba Tatsurou and Shiba Miya. He is eleven months older than his younger and only sibling Miyuki. His birthday falls on April 24th. They are often mistaken as twins for being in the same school year, though sometimes they are not immediately recognized as siblings in general.
Prior to the beginning of the series, their father remarried six months after their mother's death; with the siblings now living on their own in a house which is described as a place that vastly exceeds the average size.
From a young age, one of the only things in which Tatsuya showed any enthusiasm-like qualities was in Magic Engineering and CAD development. He has an aptitude for them and has continually displayed his interest until the present day, as he is aided by the circumstances. Their house has a basement with the same floor layout as the floor above but remodeled as Tatsuya's lab. It is equipped with state-of-the-art equipment from Four Leaves Technology with plenty of space for him to develop and test any new types of Magic that he may require.
The following section contains latest spoiler. You have been warned light novel-only readers.Proceed at your own risk.
|“||He was not one of them. Even though the blood of the Ten ran through his veins, he was never considered one of them.||”|
—Tatsuya thinking to himself, Volume 4, Chapter 14
Tatsuya is a child born of the Yotsuba family. From birth he was the apparent heir for the Yotsuba Family; but after the birth of his sister Miyuki and the discovery of his lack of ability to wield magic as it was intended, he was reduced to being Miyuki's Guardian. Despite the facts of his parentage, he isn't accepted as a legitimate member of the family by many due to the fact that he cannot wield magic freely; the two types of magic he can freely wield are not considered magic by the family's standards due to their nature of only 'destroying' and 'restoring' information, not 'altering' them.
In the present time, aside from his two natural forms of magic, he is only able to use imitation and theoretical magic; something which can be ascribed to his other unique abilities and superior intellect. Despite this deficiency he has taken advantage of his physical prowess and his superpowers to become Miyuki's Guardian, which is considered to be a job of the highest importance in the Yotsuba Family. His combat prowess has also become respected enough that he is now a primary combatant of the Yotsuba Family.
Artificial Magician Experiment
- Main Article: Reminiscence Chapter
Tatsuya's Magic Calculation Area is dominated by his powerful innate abilities, such as Decomposition, Regrowth and Elemental Sight. It is due to this imbalance that he is unable to use any other form of magic. So, to enable him to be able to use other magic spells, specially the Systematic-Type Magic, his mother, Shiba Miya, and her younger-twin sister, Yotsuba Maya, performed the Artificial Magician Experiment on the 6-year-old Tatsuya. Miya used her unique and forbidden Outer-Systematic Magic Mental Design Interference, forcibly altering the area in the consciousness that is responsible for strong emotions (called the Limbic System) and installed a Magic Calculation Model in an attempt to create an Artificial Magic Calculation Area.
However, the strain of the operation resulted in Tatsuya losing his ability to feel any type of strong emotions except for those regarding his sister. Even with this exchange for the installation of another Magic Calculation Area which granted him the ability to utilize normal magic (albeit at a significantly lower speed and power) it was still insufficient for him to be regarded as a 'true magician' by the Yotsuba's.
An additional side effect of this procedure was for Tatsuya to develop a perfect memory, allowing him to recall all of his memories with complete accuracy ever since the day of the experiment. 
It was later revealed by Maya that the operation was in fact to modify Tatsuya so he would not lose control of his emotions and become a berserker, destroying the world with his magic. In order to ensure that Tatsuya had something that he was attached to, Miyuki in this case, Miya removed all his emotions, but for some reason, that was beyond Miya's and Maya's understanding, he kept his love for Miyuki. 
Revelation of the past
- Main Article: Yotsuba Succession Chapter
The Yotsuba originally celebrated his birth, but due to the destructive potential of his magic, Kuroba Juuzou proposed the idea of killing the new-born baby, Tatsuya, but he was protected by Yotsuba Eisaku. 
When Tatsuya was a baby, he was raised to be a warrior. As early as when he was able to stand up, he was subjected to training in the optimization of his body. Tatsuya soon became able to walk and the combat training began. No matter how hard he cried and screamed, his will was ignored. As the family always resorted to locking him up, Tatsuya soon gave up on his rebellious attitude. Starting from killing a wild animal, then a military grade dog, then military strengthened animal, and finally a living soldier.  Tatsuya first killed a man when he was six, immediately after the artificial magician experiments. He sank in a skilled 30 year old combat magician in a pool of his own blood from the very start in combat, neither out of an accident nor a surprise attack. 
After Yotsuba Eisaku passed away, Maya took over the position of Family Head. Then, Maya and Miya performed the Artificial Magician Experiment on Tatsuya. Later Tatsuya was assigned as Miyuki's Guardian. 
Revelation to the world
- Main Article: Ten Master Clans Conference Chapter (I)
Maya announces that Tatsuya is her son and announces Tatsuya and Miyuki's engagement, Tatsuya is freed from the position of Miyuki's Guardian. He is then formally recognized as a Yotsuba, though his family name is kept as Shiba for now. 
- Main Article: Taurus Silver
Tatsuya is in fact half of the enigmatic Mr. Taurus Silver - the far famed Mr Silver (ミスター・シルバー) renowned as a genius engineer who advanced CAD software technology by ten years within one short year. Currently, "Taurus Silver" heads the Third Division of Four Leaves Technology.
The name of Taurus Silver was used for several reasons. First, Tatsuya was not of age when he developed the Loop-Cast system that Silver is famous for; legally, it would be impossible for Tatsuya to patent any of his inventions and developments without being of age. Second, Maya wished to keep information about Tatsuya, a mere Guardian under the Yotsuba, under wraps as much as possible; having his real name attached to inventions and state-of-the-art technology would have been inconvenient (as too much attention would be placed on him and by extension, Miyuki). It seems there is a plan discussed by which Tatsuya will finally be allowed to use 'Shiba Tatsuya' for his inventions after graduation from First High School.
Special Officer Ooguro Ryuuya
- Main Article: Ooguro Ryuuya
People Identifying Tatsuya or His Alias
In Volume 17, Tatsuya's identity as a member Yotsuba and furthermore as the son of Maya was made public.
- Yotsuba Maya - It is by Yotsuba Maya's permission, that Tatsuya is allowed to be affiliated with 101 Independent Magic-Equipped Battalion (military) where he uses the name Ooguro Ryuuya, and is also the unregistered Japanese Strategic-Class Magician [also known as "Mahesvara" by many]. As Head of the Family, she has permitted that Tatsuya work for FLT as Taurus Silver.
- Hayama, as Maya's confidante, knows about his other aliases as well.
- Some other members of the Yotsuba Family were mentioned to also know about Tatsuya being used not only as a tool but as a weapon. However, it has not been mentioned who these people are, and whether the Yotsuba know if he is (part of) Taurus Silver. Members of the Yotsuba such as Shibata Katsushige as well as Tsukuba Yuuka know that he is Taurus Silver, and that he helps largely to the income of the Yotsuba Family. Also, they are well aware of his powers and of his identity as Mahesvara, his participation in the Battle of Okinawa as well as in the Yokohama incident as a Special Officer of the battalion 101 
- Kudou Retsu - Knows that he is the son of Yotsuba Maya, though he first determined Tatsuya as Miya's son before the public declaration of Maya. Retsu knows that he serves in the 101 Independent Magic-Equipped Battalion (military) as a Strategic Class Magician. He might know more about him than Tatsuya himself.
- Shiba Miyuki - knows he is Ooguro Ryuuya, Japanese Strategic-Class Magician, part of the 101 Independent Magic-Equipped Battalion (military), (part of) the mysterious inventor Taurus Silver, and a member of the Yotsuba Family.
- Sakurai Minami - When Tatsuya mentioned that he was a Strategic-class Magician to Minami, she did not seem surprised; so it can be assumed that she was informed about some of his secrets and identities before being assigned as Miyuki's guardian.
- Most of officers of the 101 Independent Magic-Equipped Battalion know him as Ooguro Ryuuya, a Japanese Strategic-Class Magician, a part of the 101 Independent Magic-Equipped Battalion (military), but some are aware of his other identities as well, like the mysterious inventor Taurus Silver, and a person from the Yotsuba Family. Though the information about his aliases is probably contained to prevent any possible leaks from the military's side.
- Mibu Yuuzou - Mibu Sayaka's father; heard things about Tatsuya from Major Kazama but we don't know the extent of what he knows.
- Raymond Clark affirmatively knows that he is an unregistered/classified Japanese Strategic-Class Magician with the ability to use Material Burst and that he is a part of the military. He may also know that he is a member of the Yotsuba.
- Chiba Erika knows that he is from the Yotsuba Family (she has learned this ahead of everyone, by voicing some of her speculations in front of Tatsuya, and not being denied), a Special Officer in the 101 Independent Magic-Equipped Battalion under Major Kazama's command and also that he can use the magic "Regrowth". She might've speculated that he knows and can use all 16 Cardinal Codes (was present at the time when Tatsuya discussed it with Leo).
- Saegusa Mayumi knows that he can use the magic "Regrowth," saw him using "Decomposition," knows that he is a Special Officer in the military under Major Kazama and initially speculated that he was from an Extra family, the ancestors of whom were bearing the number four in their name after she tests his reaction with her bodyguard's name. Though, now she is aware of his identity as a Yotsuba.
- Saegusa Kouichi suspected that he is a member of the 101 Independent Magic-Equipped Battalion and that the squad has links to the Yotsuba. Now he is aware of his identity as a Yotsuba.
- Shibata Mizuki knows that he can construct Magic Sequences without needing to construct the Activation Sequences (Flash Cast), is able to use the magic "Regrowth" and that he is a Special Officer under Major Kazama, may speculate that he knows and can use all 16 Cardinal Codes (been there at the time when Tatsuya discussed it with Leo).
- Saijou Leonhart speculates that he knows and can use all 16 Cardinal Codes, knows he can use the magic "Regrowth", knows that he is a Special Officer in the military under Major Kazama, and that he is in the 101 Independent Magic-Equipped Battalion.
- Yoshida Mikihiko knows that he is a Special Officer in the 101 Independent Magic-Equipped Battalion under Major Kazama's orders and that he can use the magic "Regrowth", might have speculated that he knows and can use all 16 Cardinal Codes (was present at the time when Tatsuya discussed it with Leo). He should know, but probably fails to believe it, that Tatsuya is capable to "comprehend any magic design that I can 'see', which allows me to read the details behind any Activation Sequence and to provide an in-depth analysis of the Magic Sequence."
- Watanabe Mari, Ichihara Suzune, Chiyoda Kanon, Isori Kei, Mibu Sayaka, Kirihara Takeaki and Mitsui Honoka know he can use the magic "Regrowth" and know that he is a Special Officer in the military under Major Kazama.
- Kitayama Shizuku knows that he is a Special Officer in the military under Major Kazama. She also may know more, depending on what Raymond Clark told her about Tatsuya.
- Juumonji Katsuto knows that he is a Special Officer in the military under Major Kazama and had suspected that he is a member of the Ten Master Clans before the revelation to everyone that Tatsuya is Yotsuba Maya's son.
- Chiba Naotsugu knows that he's a soldier in the 101 Independent Magic-Equipped Battalion with connections to Major Kazama and wields powerful magic for a high-schooler.
- Ichijou Masaki knows that he is a Special Officer of the 101 Independent Magic-Equipped Battalion.
- Nakajou Azusa suspects that he is Taurus Silver.
- Ono Haruka suspects that he may have connections to Fujibayashi Kyouko and possibly the National Defense Force.
- Angelina Kudou Shields speculated that he is an unregistered/classified Japanese Strategic-Class Magician and that he was part of the military, but changed her mind and decided that he was a Mental Interference Illusionist.
- Edward Clark knew Tatsuya's identity as an unregistered/classified Japanese Strategic-Class Magician and that he was part of the military, and as a genius CAD engineer Taurus Silver.
Magic Limiter Pledge
Due to the MI magic Pledge, Miyuki is made as Tatsuya's limiter and key. The leader of the Tsukuba Clan, Tsukuba Touka was the magician who used Pledge that created the seal that limits the powers of Tatsuya through Miyuki.  This spell limits Tatsuya's mental activity and stops him from using his full abilities. When the limiter is released, freed Psions that are even visible briefly surrounded him in a blinding maelstrom of light. The full effects of this seal are currently unspecified and thus it's unknown if it affects his ordinary magic talent or limits his ability to use his natural magics, but it plausibly makes him unable to use his Strategic spell and blocks his access to his Psion reserves.
While Miyuki is limiting her brother's abilities, her magic ability is also partially sealed as half of her Magic Power is used to seal her brother's power. This causes her magic to escape her control occasionally when under emotional stress, mostly resulting in accidentally lowering the temperature in the surroundings whenever she is upset.
Silver Horn Custom "Trident" (トライデント)
A Specialized CAD based on the long-barreled Silver Series Silver Horn. It is equipped with cartridges for most of Tatsuya's high-level Decomposition magics. Tatsuya has used this CAD to cast high precision magic, decomposing needle-sized holes which target his opponents' nerves and blood vessels to incapacitate and cause severe pain. It is customized specifically to activate three consecutive magics into one Magic Sequence. In the Battalion, "Trident" is the name given to this merciless triple Decomposition magic as well as the CAD that performs this. It is Tatsuya's favored instrument. This CAD has interchangeable cartridges that can be pre-loaded with different types of magic. 
A large caliber rifle CAD designed specifically for Tatsuya to use with the Strategic Level Decomposition Magic "Material Burst." Third Eye does not fire a physical projectile, thus acceleration and movement magic sequences are not needed. The rifle is connected to a satellite to allow for precision targeting. With this CAD enhancing his own Elemental Sight, Tatsuya was able to hit a 50mg drop of water (1/20th of a milliliter) from 80 km away and the flag mast of a ship many hundreds of kilometers distant. Due to its nature as the only weapon with which Material Burst can be used reliably and quickly ata long distance, the key card to the CAD case is kept by Major Kazama; the CAD itself is maintained by the engineer Captain Sanada. Captain Sanada is also the person that keeps the voice-recognition mechanism's password: in the light novel, the access code is "Vanity of vanities, all is vanity"  (a Biblical reference to a recurring sentence in the Book of Ecclesiastes); in the anime, it is "Form is Emptiness, Emptiness is Form"  (a famous saying from the Heart Sutra, one of the best known and most popular Buddhist prayers). It is kept at the Independent Magic-Equipped Battalion's headquarters.
Lance Head is the CAD attachment dedicated to Baryon Lance. This CAD is an upgrade from Silver Horn Custom "Trident" (トライデント), using blade attachment that Tatsuya used to perform Baryon Lance during Yotsuba's new year gathering. This CAD enables Tatsuya to perform Baryon Lance easy. Lance Head doesn't resemble Silver Horn custom "Trident" (トライデント), but this CAD has a metal pile (spear head) at the end of it that is about 15 centimeters long. This CAD Tatsuya used for the first time in combat when he fought again Juumonji Katsuto, when he comes to force Tatsuya to join Dione Project.
Originally designed by Tatsuya and was later enhanced by Captain Sanada Shigeru; this suit has several abilities, including being bulletproof, heat resistant, shock resistant, and resistant to biological and chemical weapons; and it also sports a simple motion supplement system. A Flying Device is also attached to the belt; when coupled with the shock resistance function, it can completely nullify recoil, so the operator can accurately fire weapons while in the air. A platoon of the 101st (commanded by Captain Yanagi) is equipped with these suits.
- He is in possession of a Magatama-Class Relic, which is being researched by the FLT's 3rd Research Division Lab, his subordinates as Taurus Silver.
- He has also used a grenade canister, knives, guns, bikes and a car, showing his resourcefulness.
- Through Kokonoe Yakumo he has learned how to use unusual projectile weapons such as marbles, although it was noted that he required more training on this skill.
- He owns an electric motorcycle and a bulletproof car.
- Public Morals Committee - April 2095 ~ March 2096
Tatsuya became almost as famous as Mari herself due to his abilities. He had the highest number of incident encounters and therefore the most apprehensions among committee members.
- First High School Student Council - April 2096 ~ Present
His skills are so great that he has to leave early to allow other members to carry out their duties, otherwise he would be running the Student Council alone. When he first joined the Student Council in 2095 he was on the Public Morals Committee; but proceeding into the following year he was promoted to Vice President as per Miyuki's wishes.
- Nine Schools Competition - AD 2095 & AD 2096
He was a part of the engineering team and was lauded for the athletes in his care winning First Place for every event he was in charge of. Tatsuya also participated in Monolith Code, and was responsible for winning First Place while beating Ichijou Masaki in a head-on confrontation.
He was a part of the Thesis writing team, aiding Ichihara Suzune. He was responsible for the calibration of the magic techniques used during the demonstration.
Magical abilities aside, Tatsuya could be said to be one of First High's most outstanding students, coming in first place on the theory portions of the exams every single time. His average in the theory portion during his early first year was easily a dozen points higher than the second place score, which belonged to his sister Miyuki. Over the course of the series he has maintained distinctions and his grades have yet to falter, something that could be owed to his intellect and encyclopedic knowledge.
- Shiba Tatsuya's personality, equipment, names and abilities are heavily based on the god Shiva (Mahesvara). Shiva is one of the most revered and fascinating figures in Hindu mythology; he is the god who represents everything outside the established system, described as being both the God and the Devil in one and is heavily worshiped and feared. Shiva is held to be the Supreme God within Shaivism, one of the four largest sects within Hinduism. His weapon is a trident, which is also the name given to Tatsuya's ultimate weapon.
- His nickname [The Destroyer] or [God of Destruction] was given to him by Raymond Clark, one of the Seven Sages.
- Tatsuya has admittedly called several female characters beautiful in different degrees in his thoughts, though he has never shown any trace of arousal or attraction, as well as outward embarrassment, regardless of the situations or how a female character presents themselves to him.
- Tatsuya's voice actor is Yuuichi Nakamura, the same person who had voiced Kyousuke Kousaka, the male protagonist of Ore no Imōto ga Konna ni Kawaii Wake ga Nai. Many fans have found this humorous due to the fact that Shiba Miyuki's voice actress is Saori Hayami, the same person who had voiced Ayase Aragaki of the same show. Ironically, Ayase would often criticize Kyousuke due to his sis-con personality. And Kana Hanazawa, who voiced Ruri Gokou, is also the voice actress of Saegusa Mayumi. It's another coincidence because both girls have harbored romantic feelings for the main protagonist.
- Tatsuya and Miyuki appear on the commercial board of a building in Accel World Episode 6.
- It was mentioned in the Summer Holiday Chapter that Tatsuya's body was covered with scars all over, except for his head.
- It may be a coincidence, but Tatsuya's initials are "ST", the reverse of Taurus Silver, "TS". (Note that in Japan, family names are typically said first, e.g. Shiba Tatsuya)
- Similarly, the writer Tsutomu Satou's initials are "TS" as well, although this too may be a coincidence.
- Despite only being seventeen, many people who personally know Tatsuya assume that he is older than his actual age; Fujibayashi being one of them. The only exception is Mayumi who compared him to a child.
- His speech mannerisms could be said to rival even those living in the upper class society.
- Although Tatsuya was stated to be mundane looking, he has attracted the affection of three women that are considered incredibly beautiful: Miyuki, Mayumi, and Honoka.
- In a character popularity poll held in the official anime website of Mahouka, Tatsuya was voted by fans as the most popular character in the series, amassing a total of 6,851 votes. Miyuki was ranked 2nd while Mayumi was ranked 3rd.
- ↑ Someone with a sister complex