All spoilers regarding the first 11 volumes are unmarked. Examples pertaining to volumes 12 onward can be spoiler tagged if deemed necessary.
Characters in the The Irregular at Magic High School series.
- Voiced by: Yuuichi Nakamura
Year: 1st (Volume 1~11), 2nd (Volume 12~)
- Accomplice by Inaction: The novels' narration makes a point of telling us that, had Tatsuya known about the plot to bomb a stadium full of innocent people, he would have done nothing to stop it although he was fully capable of doing so.
- Similarly, he's unable to do anything when his Course 2 friends are ridiculed. Fortunately, Erika intervenes.
- Action Hero: Super-soldier and one of the strongest fighting mages in the world.
- Adaptational Nice Guy: He is more affable and compassionate in the anime adaptation. Also, most of his internal narration was cut, so his attempt to act like a normal person comes off as less of an act.
- Affectionate Gesture to the Head: His default method to soothe Miyuki.
- Almighty Janitor: He constantly outperforms Course 1 students despite being a Course 2 student, due to poor results in practical testing. However, it turns out that the criteria used for testing practical magic ability is faulty for irregulars like Tatsuya.
- Almost Kiss: Twice. Miyuki nearly kissed him while he was sleeping and they needed to be very close in volume 11 for Miyuki to kill a Parasite.
- Aloof Big Brother: Was this to Miyuki until she decided to get closer to him.
- Always Someone Better: A lot of people got massive inferiority complexes after seeing his skills.
- Anti-Hero: The Pragmatic variation. On the one hand, he is a rather kind guy, and on the other, the lack of strong emotions and the constant need to reconcile with the clan because of Miyuki, made him cynical and ready to do violent deeds.
- Anti-Magic: He is able to use the two strongest Counter Magics Gram Demolition and Gram Dispersion. He also found a way to use Cast Jamming without Antinite. Taken Up to Eleven with his new magic Gatekeeper, where he completely blocks a magician from using magic.
- Animal Motifs: Dragon. His Code Name, Oogura Ryuuya means Great Black Dragon.
- Asexuality: He has almost no sexual lust. He can still feel physical arousal, but avoids actions and thoughts that would cause it.. Moreover, his sister is the only person who interests him; whom he himself says that the love for her is stronger in him than the love for the opposite sex.
- Badass Boast: Gives one before going to fight Blanche's Leader and his minions.Mayumi:... Tatsuya-kun, are you planning to fight them?Tatsuya: That's an incorrect way to put it. I'm not going to fight them, I am going to annihilate them.
- Badass Bookworm: Despite being his badass self, he got the top score on First High's written exam, has an extremely large knowledge of pretty much everything, and he's always looking into things. Miyuki even finds him digging into information on the so-called Philosopher's Stone. His skills immediately get him asked to join the Thesis Competition (bookworm competition) when he hadn't even applied.
- Badass Fingersnap: Combined with volume amplification to beat Masaki in Monolith Code.
- Be Careful What You Wish For: After the events of Yotsuba Maya's kidnapping the Yotsuba family agreed to the use of Yotsuba Miya's Mental Interference Magic on her own unborn son. The idea was to create the ultimate magician, a person so powerful that he could protect the Yotsuba forever and prevent anymore tragedies such as the loss of over 30 members of the Yotsuba clan in their private war with Dahan including the deaths of key individuals such as the Clan Head. To put it bluntly it worked. Tatsuya was born with the power to literally destroy the world. The subsequent operation to neuter his emotions was to prevent his magic from accidentally going out of control due to an emotional outburst. A large number of the Clan including several branch family heads were terrified of Tatsuya's power. They wanted a magical demigod and got one only to realize that they had a ticking time bomb on their hands. They had planned to execute Tatsuya as an infant only to be overruled by the then Clan Head. Their contemptuous treatment of Tatsuya is due to their bitterness at having their hopes fulfilled in such a manner.
- Being Watched: Sometimes he doesn't even need to use Elemental Sight to know it.
- Beyond the Impossible:
- Flight magic was considered impossible using Modern Magic (it could be done with Ancient Magic) until he discovered a way for Modern Magicians to do it.
- Elemental Sight allows him to read activation sequences, which is impossible for other magicians, so they can't use Gram Dispersion or his version of Cast Jamming.
- Beneath the Mask: He considers most people various degrees of expendable, and others instinctively understand this when they see him angry.
- Big Brother Instinct: Endangering Miyuki is the only way to genuinely anger Tatsuya. The one time Miyuki's life was actually in danger he went on a rampage so devastating it earned him the nickname Mahesvara from the Chinese. He killed their guys so hard an entire nation dare not even speak his name. At the same time, his concern for the happiness Miyuki comes to such an extent that it seems to be ready to truly love her as a woman if need be. As a result, he did not even reject her after the declaration of love, saying that he might be able to fall in love with her in the future.
- Big Brother Is Watching: Literally. Can keep an eye on Miyuki at any time with Elemental Sight. Not that she minds.
- Big Damn Heroes:
- To save Erika and Mikihiko from the parasite.
- Also to save Mizuki from being possessed.
- Blood-Splattered Warrior: After killing a terrorist at Yokohama.
- Bodyguarding a Badass: As Miyuki's guardian.
- Born Winner: Even though not everybody can use magic and some lineages are more powerful than others, Tatsuya qualifies. The Yotsuba is the most powerful clan among the 10 Master Clans in Japan. There are two magician lineages in the Yotsuba clan. Some of them are born with a strengthened mind manipulation magic (Miyuki and Miya) and the others are born with a very strong ability. Tatsuya and Maya belong to the latter category.
- Boyfriend Bluff: Invoked. When out on the town, he and Miyuki pretend they're a couple to protect her from unwanted attention.
- Bridal Carry: Done to Miyuki from time to time. Who totally loves it.
- Brilliant, but Lazy: He could escape the Yotsuba's influence eventually, but his dislike and fear of them simply isn't strong enough to motivate him to do so. So meanwhile, he kills people for them and guards Miyuki.
- Broken Ace: His practical school results aside, he is a Teen Genius and is good at every sports, he is so good that his friends joke that he's omnipotent. But most of his friends arent aware of his troubled past and how Tatsuya views himself because of this operation.
- Brother-Sister Team: When working with Miyuki.
- Bullet Catch: Played with in Volume 7, he used his Decomposition on the physical body of the bullets, giving the impression that he was catching them.
- Bullying a Dragon: Many people take his Course 2 status to mean a lack of ability; while wiser heads acknowledge that regardless, his combat ability is first class, some never do learn the lesson. Most egregious though are those connected to the Yotsuba family. They are well aware that Tatsuya is a strategic class magician and thus Person of Mass Destruction which is bad enough. The fact that his adoring sister Miyuki is slated to be the next head of the House and is a powerful magician in her own right seals the deal. Just how well do they expect to be treated when they have heaped nothing but scorn and contempt on her beloved brother when Miyuki ascends to her position as the head of the Yotsuba?
- Byronic Hero: His vast practical capabilities are matched only by his inability to deal with uncomfortable subjects in ways other than denial or murder.
- Bystander Syndrome: Tatsuya feels sympathy for the victims of Course 1 bullies, but doesn't do anything to help them until Miyuki prods him into it. He's very 'all or nothing' that way.
- Celibate Hero: Justified. He can't feel strong emotions like love
- Chessmaster Sidekick: During the Nine School Competitions, as an engineer.
- Chick Magnet: One of the most striking examples of this in the anime, it seems, almost all of the heroines of the show deeply in love with him, including even his own sister. He became more popular with girls after demonstrating his prowess during the Nine Schools Competition.
- Child Soldier: He joined the 101st Battalion since he was 13. His training started at a very early age and included fighting animals. He fought and killed an 30 year old man when he was just 6 years old!
- Clueless Chick Magnet: His lack of a normal range of emotions means that he often misses the hints that a good number of the girls/women around him are romantically interested in him. When clearly faced with a declaration of love, he demonstrates himself to also be a Celibate Hero.
- Code Name: Oguro Ryuuya.
- Cool Gun: His CADs, Silver Horn, Third Eye, and Trident, are shaped like one.
- Commonality Connection: With Ayako, due to their similar magics.
- Covered with Scars: Has many scars all over his body though they're hidden by his clothing.
- Curb-Stomp Battle:
- Tatsuya defeats Vice President Hattori in less than 5 seconds during their first battle. Made somewhat ironic by how the latter planned to use speed abilities to gain the upper hand, and stating that whoever attacks first is pretty much the winner.
- He single-handedly curb stomped the Great Asian Alliance army that invaded Okinawa three years before the start of the series after some of the soldiers allied with them shot Miyuki. He had the 101st with him, but he was so enraged that he practically decomposed everything before it could touch him or before his allies could shoot it, all while restoring any allies that fell in battle. He concluded the affairs by field-experimenting his new shiny magic theory - the "Material Burst" for the first time and proving beyond a shadow of a doubt that, regardless of the Yotsubas' beliefs regarding his ability as a magician, he was stronger than all of them and the only reason he didn't bother to correct them was because he only cared about Miyuki.
- Deadpan Snarker: Often, he is the only sensible person among those around him.
- Death Glare: He gives one to a committee organizer who he catches trying to upload a virus into Miyuki's CAD in episode 17. He's only stopped because Retsu Kudou personally came to the inspection area to see what was the ruckus was, the latter also being displeased that there was someone like that working for him.
- Declaration of Protection: To Miyuki. Many times.
- Disintegrator Ray: Can perform this with his Decomposition magic.
- Ditzy Genius: A downplayed example. For example, he knows that incest is unacceptable socially, and he knows that people don't like hearing about unacceptable, but these pieces of knowledge don't quite connect in his mind. Therefore, he doesn't realise that joking about incest might be a bad idea. Or that Miyuki might be forced into an Arranged Marriage, or just how unlike a civilian he acts, etc.
- Hates Being Touched: He instinctively panics upon being touched, or when any physical interactions go in a surprising direction.
- Don't Make Me Destroy You: When Erika, his friend, is about to reveal the fact that she knows about his true identity, he orders her to stop speaking. This is because if she didn't, he would have to kill her to protect the secret.
- The Dreaded: Those who know his true powers, most notably the Chinese, are very scared of him. Also, in volume 17, he becomes this to the school after the reveal of their identity as Yotsuba
- Earn Your Title: Got named Mahesvara after the battle of Okinawa where he restored soldiers who were fatally injured and decomposed his enemies completely.
- Emotion Suppression: He can't feel fully his emotions due to the process that made him an Artificial Magician, leaving him somewhat disconnected from the others his age.
- The only one which stayed intact is his: "brotherly love"
- Energy Ball: Gram Demolition is a cannonball of Psions.
- Epic Battle Boredom: Was decomposing his enemies without being attacked even once at 13.
- Everyone Has Standards: He doesn't judge Miyuki for magically lobotomizing their enemies, but he quietly prevents the spells from connecting. It's unclear whether this was to protect her perceived moral purity or out of empathy for the victims because he knows what being MindRaped is like.
- Experienced Protagonist: He is still training and becoming stronger, but he was already one of the strongest magicians at the start of the story.
- Fighter, Mage, Thief: In Monolith Code, as the thief.
- The Gadfly: Not even brainwashing completely stemmed his desire to fuck with people. This is one reason Miyuki is so confused about their relationship- she is his favorite target, and he never tells her whether he's being sincere or not.
- Gadgeteer Genius: He invents a lot of interesting CADs that prove to be useful for his friends, such as the flying spell Miyuki uses during the Nine Schools competition.
- Good Thing You Can Heal: His Self-Restoration will automatically restore his body when he is significantly injured or when an abnormality occurs which reduces his combat ability. He can restrain it through conscious control to punish himself or prevent others from noticing his ability.
- Goal in Life: His dream is to develop a Gravity Control-Type Thermonuclear Fusion Reactor so that Magicians won't be treated as mere weapons.
- Grew Beyond Their Programming: Tatsuya is a lot more "human" than he was when he was young. (Or better at acting human, anyway.) This implies that his issues are partly because of magic and partly the natural result of someone being raised without affection.
- Guns Akimbo: He is one of the few magicians who can use two CADs at the same time. He actually has three CADs—twin pistols and a bracelet-type—during the Newcomers Monolith Code competition.
- Gun Fu: In anime episode 16, to destroy Masaki's Air Bullets.
- The Gunslinger/Mage Marksman: Very good with guns and gun-shaped CADs.
- Healing Factor: To the point of being able to survive a shot through the heart like it was nothing.
- Healing Shiv: He can apply his Healing Factor (Regrowth) to anyone by shooting them with his gun.
- Heroic Self-Deprecation: He feels that Leo's friendship is wasted on him because, being almost emotionless, he can't appreciate it as much as a normal person would.
- Homage: To Batman in volume 12.
- Humble Hero: Despite his strength and his talents he thinks he is nothing special. This is because A) he thinks that heroes must have selfless motivations to be heroic, and B) all Clan Guardians are engineered and expected to be on par with trained soldiers. Indeed, one of the reasons his exploits draw so much attention is because onlookers don't know he's Clan-blooded.
- Hyper-Competent Sidekick: Hence the reason why most of his Senpais abuse him.
- Hypocrite: In the Conference arc, Tatsuya says that the magical community does not enforce Arranged Marriages (only encourage them). This prompts Mari to ask how much choice Tatsuya and his sister had in who they were married to.
- I Am Not a Gun: He's getting there...slowly.
- I'm Having Soul Pains: Can inflict this with Far Strike.
- Improbable Aiming Skills/Spread Shot: Can snipe 36 targets simultaneously.
- I Lied: He pumps one of No-Head Dragon's leaders for information before killing him.
- Incest Subtext: Tatsuya plays it for laughs. Nevertheless, series has a lot of frank ship tease between him and Miyuki, more than any other girl. And although in the future it is explained by a number of the nuances of their past, overly intimate nature of their relationship and regular his thoughts about her beauty may directly have such subtext..Fortunately, he was not overcome by sexual desire even with such a peerless beauty sharing the same bed with him. That did not mean he had not felt anything at all, however.
- Innocent Innuendo: In book 23, he remarks on the 'intimacy' of the ritual he and Miyuki are about to perform. To Miyuki's surprise (and disappointment), he means spiritual intimacy.
- Invincible Hero: He always loses against Yakumo but has yet to lose against other opponents. He wishes to remain unbeatable so that Miyuki will be proud of him.
- I Just Want to Be Free: All he wants is to live a nice peaceful life with his sister. Unfortunately, there are a lot of factions who want to control them, and he can't kill all of them without plunging the world into anarchy. Hence, the series' plot is about his efforts to civilly maneuver away from these factions and keep his powers a secret. Naturally, he fails.
- Jerkass Ball: Although the author mostly tries to portray Tatsuya as a Nice Guy and a very pacifist man, sometimes he gets demonstratively cynical or pro-nationalistic scenes only so that the development of the arc does not go along a peaceful path, and Tatsuya constantly reminds about his "emotionless" to the reader.
- Knight Templar Big Brother: If you threaten Miyuki in any way, your life insurance better be paid up.
- Kung-Fu Wizard: Practices Ninjutsu, although it is considered Ancient Magic.
- A Lady on Each Arm: Courtesy of Miyuki and Honoka.
- Lightning Bruiser: Strong, fast and with a Healing Factor. Even his sister sometimes uses dangerous spells against him, because she knows that he will instantly recover from them.
- Milking the Monster: No one (except Miyuki) really wants Tatsuya alive, as his very existence is a risk to the world, but since he's not about to let anybody kill him, various factions find it useful to have him around. Would you dismiss someone who could duplicate jewellery at a moment's notice?
- Mind Rape: Was subjected to one as a child, apparently while conscious. It's one reason why he's so unwilling to leave the Yotsuba, who perpetrated it.
- Mr. Exposition: The author loves to report details about the world and current events through Tatsuya's speech and thought.
- More Than Mind Control: Miyuki's influence doesn't change Tatsuya's personality so much as it dilutes it to human levels. (He's still introverted, but he doesn't completely cut himself off from others.) This implies that the operation 'only' amplified his nature through crippling his capacity to be affected by others' treatment of him.
- Mundane Utility: He knows his power level means he can basically say whatever he wants to whoever he wants. What are they going to do, kill him?
- Names to Run Away from Really Fast: Mahesvara, the destroyer and restorer of worlds.
- My Greatest Failure: He will never be able to heal himself from what the Yotsuba did to him, and he knows it.
- Nice Guy: Despite his stoic and aloof personality, Tatsuya is unfailingly polite and honest to everyone he meets. Miyuki once said he can be nice to a fault in the strangest of ways.
- Not Blood Siblings: Played with. Upon his age of majority, the Yotsuba house declares that he is secretly the son of Yotsuba Maya making him Miyuki's first cousin. As marriage between cousins is legal in Japan, Tatsuya is then engaged to Miyuki. This is a legal fiction cooked up by Yotsuba Maya to legalize the sibling marriage. Miyuki is an enhanced magician and thus their pairing would avoid the usual drawbacks of incest with regards to deformities in their children.
- At the same time, this move still has its own nuances, as Shiba siblings' aunt Maya and mother Miya were identical twins, their genes are the same, so even if Tatsuya really is Maya's son, he is genetically as close to Miyuki as a half-brother would be.
- Not So Stoic: Some of his inhumanity is permanent, some of it just comes from growing up with no-one but his abusive family and their employees around. He's still discovering where the limit is.
- Oblivious to Love: He rarely notices when a girl likes him. This is due to Tatsuya's lack of strong emotions.
- One-Man Army: Let's just say that he alone can stop an entire invasion of the enemy, destroying the entire enemy fleet with one large nuclear explosion, or scattering a powerful enemy spell that the enemy has been planning for years.
- One-Hit Kill: When using Mist Dispersion to decompose the whole body.
- Passive-Aggressive Kombat: The only degree to which he can express anything other than total rage. For example, during a conversation with his father, Tatsuya says calmly that he "can't hate" Sayuri. His expression says "because she emotionally mutilated me, that bitch". Similarly, during the Reminscence arc he was always quiet and obedient but clearly angry at...everyone, really.
- Person of Mass Destruction: As a Strategic Class magician. His strongest magic "Material Burst" is capable of converting matter to energy according to Einstein's E=MC^2 equation. In theory he could vaporize the Earth. Word of God even states that Tatsuya doesn't have an upper limit in decomposing substances, as long as he perceives it.note
- Please Wake Up: He did not take Honami's Final Death well at all, and continuously tried to regenerate her despite knowing it was impossible.
- Promoted to Playable: A non video game example. After the school's Monolith Code Team gets badly injured, he's forced to participate.
- Razor-Sharp Hand: Can coat his hand with Decomposition magic to tear the flesh of his enemies.
- Reed Richards Is Useless: Because the setting is very futuristic, he channels most of his intellect into dealing with magical problems. There's no real need for him to do otherwise.
- The Rival: Seen as one by Masaki and Shinkurou.
- Role Reprisal: Was played by Yuuichi Nakamura in the audio drama CD.
- Rousseau Was Right: He's soulless, but he's not a jerk unless someone gives him reason to be.
- Rule of Symbolism: Tatsuya is heavily based on Lord Shiva, the Hindu God of Universal Destruction and Recreation. His appellation, Mahesvara is another name for Lord Shiva. Shiva is himself the most powerful being alongside Brahma and Vishnu in Hindu Mythology.
- Sacrificed Basic Skill for Awesome Training: He had no childhood to speak of, so he basically threw himself into academia to avoid thinking about his very bleak familial situation.
- Savvy Guy, Energetic Girl: With both Erika and Mayumi.
- Science Hero: Tatsya personally developed their own weapons and is known as one of the best technicians in the country. Moreover, his main goal in life is to become an engineer.
- Second Year Protagonist: Starting from volume 12.
- Security Cling: He requests one from Miyuki while searching for Zhou, because her recent near-death experience made him irrationally afraid of looking away from her.
- Secret Identity: He is the software developer half of the legendary CAD technician known to the public as Taurus Silver; his mom is the sister of the current head of the Yotsuba clan.
- Secretly Selfish: He goes along with most requests/orders other people give him, but only because a) he's been conditioned to, and b) obeying is usually easier than refusing. As long as the people he cares about are safe, he doesn't really care what goes on in the world. Even his main goal of freeing magicians from military prescription is pursued because it would make he and Miyuki slightly more comfortable.
- Selective Obliviousness: It's hinted that Tatsuya knows or at least suspects the reason why Miyuki sometimes acts strangely, but he deliberately tries not to notice it, because he considers such suspicions to be unacceptably offensive.
- Single-Target Sexuality: Subverted: Miyuki is literally the single important person in his life, but he is not capable of experiencing romantic attraction even to her.
- The Sociopath: Became one after being Mind Raped in his childhood. Though not actively malicious, he can't value the lives of strangers or reliably interpret people's emotions.
- Spock Speak: He talks very formally.
- The Stoic: Largely due to not being able to show emotions any longer due to various things done to him. However, threatening Miyuki will still make him upset and he'll show you a Death Glare so terrible you'll regret incurring his wrath.
- The Strategist: His combat technique is based on this, since, due to the lack of real abilities of modern magic, Tatsuya is forced to rely on good combat strategy and his physical skills.
- Stock Light-Novel Hero: Deconstructed.
- The Invincible Hero that is so prevalent in light novels. His soul was changed when he was still in his mother's stomach, and in childhood was forced to become Child Soldier to master the most powerful magic known to man so that he could guard the Yotsuba family forever. Many people, however, fear a possible Beware the Superman scenario and would rather keep their distance from him. The Yotsuba family even created Miyuki to restrain him.
- His Stoic nature isn't by choice. To prevent him from destroying the world on a whim, the Yotsubas altered his brain chemistry and made him unable to feel any strong emotion, except for his love for Miyuki.
- Straight Man: He typically does not understand or care about his friends' social antics, and much of the series' comedy comes from this.
- Straw Vulcan: For example, he does not appreciate the council tradition of using physical documents (as opposed to more efficient electronic records).
- Strong Family Resemblance: Almost prevented. On the one hand he is very similar to his father, and on the other, he is almost no similar to his sister with the exception of hair and eye color. As it turns out in the future, it is because the genes of his sister have been specially improved to give her a perfect look. Thus, they are different in appearance.
- Sugar-and-Ice Personality: Because of the lack of strong emotions, Tatsuya may seem cold or sometimes even a cynical young man, but when he interacts with Miyuki, he immediately becomes a gentle, responsive and loving older brother. Moreover, as he lives in high school and interacts with his friends, it seems that he is gradually becoming more and more relaxed as a person.
- Super Soldier: He's an artificial magician and considered a top-secret asset of the military- equal to a strategic weapon like an ICBM.
- Talker and Doer: With his fellow engineer Ushiyama, although both are exceptionally knowledgeable. Tatsuya creates innovative prototypes far ahead of anything on the market, Ushiyama actually tests these prototypes and gets them mass-produced for the public.
- Teen Genius: Since Tatsuya from his earliest childhood was forced to engage in constant self-education and improve his analytical abilities, by the age of 15 he is a teenager with brilliant intelligence and such a speed of thought that he is able to instantly calculate any sequences in foreign spells. Moreover, he is so smart, that even his own father-scientist envies and hates him.
- Technician vs. Performer: He can technically dance well, but there's no emotion or spontaneity in it.
- Terms of Endangerment: When Miyuki was young and foolish, she once tried to command him to treat her with more intimacy. Tatsuya obeyed- because he had to- but the way he did terrified her so much she fled from the room apologizing.
- Terrifying Rescuer: The young child Kokoa merely looks at his stern face and tries to hide.
- Terror Hero: Due to the mystery surrounding his magics, people tend to be afraid when he uses them and he is fully aware of it.
- The Tease: After they get engaged, he deliberately flirts with Miyuki because he finds her flustered-ness cute.'
- That Makes Me Feel Angry: He does not see the irony of feeling sad that he can't empathize with his friend's emotions.
- Token Evil Teammate: For the student council. For example, he's the one who enacts their plan to coerce Azusa into becoming the next president.Azusas attitude was more obstinate than predicted. And just now, she looked as if she would burst into tears. If he drove her into a corner, she really might break down crying. No, there was no might, the possibility was high.
However, if he was going to give up just like that, he would never have undertaken persuading her in the first place.
- Touch of Death: His Decomposition magic at full-contact.
- Tranquil Fury: Partly due to not being able to really display emotions any longer.
- Troubling Unchildlike Behaviour: He was a Child Soldier, after all. At the age of six, he was already seeking allies. Not friends- allies.
- True Final Boss: When the group were discussing which roles they'd play in an RPG, they pegged him as this. (Well, most of them did. The others considered him a hermit sifu.)
- Tyke-Bomb: Trained since his childhood to be Miyuki's guardian, his mother even removed all his emotions save for his love for his sister so he'll do his best to protect her at any cost. The novels reveal that this was done in order to prevent him from possibly going berserk and destroying the planet with Material Burst. There was a sizable faction that thought he should be killed outright just to be safe.
- Underestimating Badassery: People looked down on him because he is a Course 2 student.
- He is also on the other end of this trope; he doubts Azusa's capability because she's so excitable. Mayumi assures him otherwise.
- Undying Loyalty: He will unrepentantly let thousands die just because Miyuki ordered him to rest. This is also why he accepts Miyuki's feelings towards him, despite not approving of incest.
- Urban Legend: Many people think Mahesvara doesn't exist.
- Unwanted Harem: In his case, it's an Unnoticed Harem. Aside from Miyuki and Honoka, Tatsuya gets borderline romantic moments with Mayumi, Erika, Lina and Pixie; all of whom have expressed interest in him on different points of the series.
- Unwitting Instigator of Doom: The "Scorched Halloween" event that he caused made the Japanese navy very concerned- especially since they didn't know the perpetrator was technically on their side- so they did some very illegal things in order to 'protect' their country. This forms the plot of the movie.
- Vitriolic Best Buds: With Mayumi. Most of their interactions are verbal sparring.
- Weak, but Skilled: He is this when he is not using his innate magics.
- What Is This Thing You Call "Love"?: Sometimes wonders what is romantic love since he can't feel it.
- Woobie, Destroyer of Worlds: Miyuki is literally his sense of life and at the same time, its guarantee. If something happens to her, he will destroy the world.
- Workaholic: He is not this trope, but appears to be it because he finds doing a lot of engineering work more comfortable than the small amount of social work refusing it would require.
- Willfully Weak: Since he must hide most of his abilities, he can't fight at full power. Granted, a few of his abilities are also not readily available to him. An example would be his Decomposition magic "Material Burst" which requires the "Third Eye" CAD in possession of the military as well as Miyuki removing her suppression effect on his power.
- The thing about "Material Burst" is that he can use it (Reminiscence Chapter), but he was also in range of the enemy's attack (ships that could launch rockets at 20km). The "Third Eye" CAD just allows him to fire "Material Burst" at a safer distance.
- Wise Beyond Their Years: Many people think Tatsuya is too mature to be a teenager.
- You Are What You Hate: His similarity to the government's crazed drone-magicians only makes him more convinced they should be eliminated.
- Voiced by: Saori Hayami
Year: 1st (Volume 1~11), 2nd (Volume 12~)
- Almost Kiss: Thrice. She nearly kissed Tatsuya by mistake (she fell) while he was sleeping. Though the situation only came about because she was tempted to kiss him in the first place. Their lips were also very close in volume 11 and 20.
- Aloof Dark-Haired Girl: Whenever things do not relate to Tatsuya.
- The Ace: Her Magic Power is very high and she can use magic with complex processes very easily.
- Action Girl: Because of her high position in the clan, Miyuki is much less involved in the clashes than her brother, but when it happens, she turns out to be as dangerous as he is.
- An Ice Person: She specializes in cooling magic.
- Anti-Magic: Zone Interference, a wide area Counter Magic. Hers is one of the most powerful in the world.
- Area of Effect: She is better with magic with a large radius.
- Artificial Human: As revealed in volume 17. She doesn't mind, because her original body is long dead and her artificiality is one reason she's so powerful.
- Barrier Maiden: Half her MCA unconsciously goes towards locking away (some of) Tatsuya's power, so he can only annihilate really big chunks of the world instead of all of it. After Tatsuya's true identity is exposed and Maya refuses to protect him from the resulting assassins, Miyuki goes 'Fuck it' and has her brain altered so it is no longerthe trope.
- Big Brother Attraction: Let's just say she loves her brother Tatsuya a lot. She so much in love with his brother, that she considers herself belonging to Tatsuya and wants to marry him. So, as Miyuki finds that her body and soul belong to Tatsuya, in his own words, she was ready to let him do with her whatever he wants. This is emphasized in Volume 11, where she declares a willingness to show Tatsuya "her hidden places" or to have sex with him.
- Big Brother Worship: Miyuki worships Tatsuya incredibly much. She even refers to him as "oniisama".
- Broken Ace: Outwardly, she is perfect. She can't really afford to be seen as anything else, since her family are bastards, everyone is (justifiably) terrified of her undisciplined magic, she is unrequitedly in love with her own brother, and there is a very real possibility she'll have to kill him to stop the world from going kaboom. Even her friends, after Miyuki's true identity is revealed, take a day or so to wonder 'Do we really want to be close to someone from that family?'
- Brother-Sister Team: When working with Tatsuya.
- Bodyguard Crush: She is in love with her bodyguard and personal servant, although Tatsuya is her own brother.
- Born Lucky: Even by artificial human standards, she came out well.
- Clingy Jealous Girl:
- She doesn't take it too well when Mari teases Tatsuya about Mibu in episode 4 which causes her to freeze up the table around the student council. And she does it again after Mari teases him about Mayumi a moment later in that episode.
- She gives green light to Honoka to go after her brother and sometimes helps Honoka out with this matter.
- Although after the news of their engagement, she tries to be more reserved, fearing that because of her jealousy she may lose the only chance to be a couple with Tatsui, she still can not hold back when she thinks he is too cold. In particular, she demonstratively begins to call her brother Tatsuya-sama, even in personal communication, to emphasize that they are no longer a brother and sister to others, so he must begin to perceive her as a bride.
- Cloudcuckoolander's Minder: She tries to lead her brother through his many heartbotomy-induced blind spots.
- Cold-Blooded Torture: To a captured member of Blanche in Yuutousei.
- Cooldown Hug: With Tatsuya after she freezes everyone during a student assembly.
- Coming-of-Age Story: The Reminscence arc is hers; it explains why she acts the way she does presently, and shows her learning about what being a Yotsuba means (as well as her growing sexuality) and deciding what she is going to do about it.
- Curb-Stomp Battle: During the mirage bat event in her 1st 9-school competition, she completely dominates her competitors (extra points for Miyuki being a junior competing in the senior event). Even after Tatsuya was asked to submit her CAD due to the complaint from other schools, after which the committee decided to leak the code to the other schools allowing them to copy the flying technique Miyuki used, she still completely floors them due to their inexperience with using said spell. What makes it golden is that she ALREADY was the number 1 player even before she decides to crush those players' pride into oblivion with the Flying spell.
- Does Not Like Men: Believes her entire body and heart belong to Tatsuya. Going so far as to be disgusted by the concept of being touched by anyone at all except Tatsuya. She also despises the mere notion of marrying anybody but her brother to the point that she breaks out of her nice-girl character in anger and emotional despair.
- Designer Babies: Miyuki was created artificially as Tatsuya's sister, so that she can restrain his strength with the help of her outstanding magical abilities and stop him if necessary. In consequence, although she has the same parents as Tatsuya, their genes are different enough that incest between them could result in a healthy offspring.
- Dude Magnet: Due to her perfect appearance, she often becomes the object of attention from guys. She doesn't like it.
- Doublethink: Miyuki's stratified upbringing essentially twisted her psyche into a pretzel. Therefore, she can both attack Tatsuya for looking at other women and tell Shizuku smilingly, a few volumes later, that her affection for him is completely unconditional.
- Eating the Eye Candy: In Reminiscence, she enjoys watching Tatsuya exercise shirtless. She feels embarrassed when he almost catches her doing this, although- being just a teenager then- she doesn't quite understand why.
- Even the Girls Want Her: It seems that Izumi Saegusa is in love with her. Moreover, Izumi even wants Tatsuya to marry her older sister, so that Miyuki will officially become her "Onee-sama".
- Everyone Can See It: It is painfully obvious to everyone except Tatsuya that Miyuki's love for Tatsuya isn't sibling love. He can't see much of anything outside of cold-calculations. Ever since Tatsuya saved Miyuki after she was severely wounded three years prior to the series, she has devoted her life to him. As a result, everything that she does, how she acts/thinks, what she is involved in or what her personality is like, etc. is because of Tatsuya. In short, everything involving/revolving around her, good or bad, is because of her feelings for Tatsuya.
- Everyone Hates Mathematics: She's not as good at mathematics as she is at other subjects, though this is highly relative. She's still exceptional at it.
- The Fashionista: Although this is not the defining character trait, she is known for wearing different stylish outfits and hairstyles. According to the illustrations and text in the series, she wears masks and hooded dresses/hooded scarves if she doesn't have hairstyles that hold her hair back to go with her outfits. Those hairstyles include ponytails, buns and headbands. Based on those illustrations and text, the author and illustrator combined outfits and hairstyles from real-life and from stuff like Disney's Frozen for all of Miyuki's hairstyles and outfits.
- Father, I Want to Marry My Brother: Several of her interior monologue throughout the series directly refers to this trope. Later in the series, they are engaged, when it turns out that has a genetically modified body, so she can become his wife, and in this regard, their aunt announces their engagement in volume 16.
- The Force Is Strong with This One: Although Tatsuya was Miyuki's slave, she always felt uncomfortable around him in a way she could never quite articulate until she realized he was a magician who could nuke her off the face of the earth. (It is the nature of Anti-Magic to not be noticed.)
- Friendly Rivalry: With Honoka and Shizuku.
- The Gift: Being from the Ten Master Clans she is naturally this, though even compared to the others she can use complex magic for mundane thing with ease and flawlessly. Amazing the others with her talent.
- Gilded Cage: The last heiress of the Yotsuba was kidnapped and tortured, so they do everything in their power to stop it from happening again. She can't even take walks alone, and the family habitually deceived her so she wouldn't get involved in any of the important stuff they were doing.
- Hair Decorations: A hair clip with jeweled snowflakes, given to her by Tatsuya.
- Hime Cut: She has the traditional hairstyle for a Yamato Nadeshiko.
- Hope Bringer: To Tatsuya. He had not expected that someone as privileged as the Yotsuba heiress would have any compassion, and realizing otherwise made him less pessimistic about people in general, enough to try making friends.
- Hopeless Suitor:She's fully aware that Tatsuya doesn't see her as someone of the opposite sex since they are blood-related. She is then informed that she is going to be married to Tatsuya when she becomes the head of the Yotsuba family, much to her extreme approval and happiness. And although she seems quite happy with the fact that, technically, it is still his sister, Miyuki said every time when the others have questioned "legend" about of their cousins status.
- Hot-Blooded: One reason why she rebelled against her family's expectations is they required her to be civil around people she hated, and to ignore their brainwashing of children who didn't fit in. Miyuki is the sort of person who doesn't feel alive if she's concealing her feelings, so around the age of 13 she basically stopped trying.
- An Ice Person: Miyuki specializes in cooling magicnote . Her cooling magic, however, is a physical manifestation of her natural mind-affecting magic. Her most powerful magic, "Cocytus", freezes the consciousness of its target. Not the target's neurons, mind—their soul. It could be considered a Fate Worse than Death.
- Incest Subtext: Contrary to Tatsuya she really means it. However, later in the 16 th volume of the novel it turns out that as a consequence of a variety of genetic experiments in early childhood, she and Tetsuya completely free from any negative consequences of inbreeding, and their aunt adopts Tetsuya and announces it to his son, effectively turning them into cousin brother and sister, thereby opening up the possibility for their subsequent marriage.
- Informed Attractiveness: Everyone calls her the one of the most beautiful girls and even her own brother has repeatedly noted her spectacular beauty. She looks very perfect, that later gets his explanation, she is an "improved" magician, so her body was maximally improved through genetic engineering. (and when seen from a Japanese perspective it's true since she is the good example of Japanese beauty, in other words Raven Hair, Ivory Skin).
- In-Series Nickname: "The Queen" and also the "Snow Queen".
- Implied Love Interest: Along with what has been said above, Miyuki is strongly implied as one of such heroines. She from the very beginning is next to Tatsuya and despite the fact that they are siblings and he does not see a woman in it, together they share most of the romantic moments in the series. Moreover, as the only close person in his life and as the only girl to whom he can have strong feelings, it is Miyuki who is jealous of him towards other girls.
- I Want My Beloved to Be Happy: Subverted: Although it would seem she perfectly understands the inadmissibility of such relationships and therefore will not try to seduce her brother, Miyuki immediately becomes an extremely jealous girl if there is the slightest opportunity to be with him.
- Not Blood Siblings: played with. Although Miyuki is certainly Tatsuya's own sister, which was confirmed by himself and Maya, their genes are different due to the fact that Miyuki was created artificially from the fertilized egg of Tatsuya's parents and subsequently genetically modified. Thus, this allows their aunt to announce their engagement as a cousins, without worrying about the health of their offspring, despite the fact that their couple will actually be an incest between brother and sister.
- Jerkass Ball: In some cases, her attitude towards ethics and violence can be reversed, depending on the needs of the story.
- Lady of Black Magic: Her magic is specialized for covering a large area and is very powerful.
- Little Sister Heroine: Very bright, almost archetypal example. However, in the future more and more implied that Miyuki purposefully playing the "role" in order to deceive his brother and convince him of the need to care for her.
- Living Emotional Crutch: To Tatsuya.
- Luminescent Blush: Every time Tatsuya compliments her, only her cheeks blush, as the trope page clearly states. Every time.
- Locked Out of the Loop: Nobody in the Yotsuba really wanted to talk about Tatsuya's mutilation, especially not Tatsuya himself, so for most her childhood she had no idea why Miya ordered him to guard her. Even in the present day Tatsuya doesn't tell her that she's an Artificial Human created to seal his powers.
- Love at First Sight: It took her no more than two weeks to fall in love with Tatsuya. The fact that he was her own brother did not really hinder this.
- Love Hungry: Invoked, since her Love Interest is her own brother, who for moral and physical reasons does not see a woman in her.
- Lunacy: Cocytus is a Lunar Magic.
- Male Gaze: Anime adaptation and especially the film, are very fond of showing her figure in tight-fitting dresses from profitable angles.
- Mafia Princess: Was one before she took a more active role in family politics, though the Yotsuba aren't literal yakuza. She was deliberately raised to be attractive and ignorant, so that she could get the family some much-needed positive PR, charm whatever husband they chose for her, and generally stay out of the way while the Yotsuba's real leaders maintained their clan's power.
- Manic Pixie Dream Girl: She suggested that Tatsuya attend school so he could broaden his horizons beyond work.
- Manga Effects: The interesting thing about this is that there are no times she makes any of the iconographic body features, actions and everything else aside from two times only in the second to last volume of year 1 (Volume 10) and they don't count as manga effects as the parts of her face and body that are exaggerated are the same parts of her younger self from Volume 8.
- Mind Manipulation: As a Yotsuba of the first lineage Miyuki inherited a Mental Interference magic. Her Cocytus can freeze minds.
- Mistaken for Romance: Her and Tatsuya, at least it's not romance for him.
- My Brother Is Off Limits: For obvious reasons. She tried to hold back for Honoka though.
- Obfuscating Stupidity: Sometimes, when she is with her brother. Given that Tatsuya has a justified reason for being as dense as he can be, she's a lot more perceptive then he is.Tatsuya: I'm always being saved by you getting angry in my place.
- Oh, Crap!: When she was young, she once saw Tatsuya smile, and she realized that he was a human being with feelings just like her. Then she realized what that said about her, who had treated him like a doormat all their lives.
- Ojou: Less obvious type 1 than Mayumi, but as the daughter of the lead of the 10 major magical clans, Miyuki has unrivaled grace, education and upbringing.
- One-Woman Army: Her AoE magic is totally suitable for this task. She cleared out an entire warehouse full of armed soldiers, with one spell.
- Out of Character: Moment: Despite her "apparent" infantilism and spoiledness, in a series of important moments for the plot, Miyuki becomes very serious or even cynical. [[Spoiler: Although it is believed that this is her original mature personality, the plot depicts this rather controversially.]]
- Patient Childhood Love Interest: Subverted: Although Tatsuya is her own brother and is always with her, for a long time she simply enjoyed his presence and at least thought that she did not really need a real incestuous relationship with him. However, the family and girls in the new school think differently.
- Perfectly Arranged Marriage: To Tatsuya. Although technically Tatsuya her brother, she was so heavily genetically modified that her theoretical incestuous relationship with his brother will not have any negative consequences It may also be somewhat one-sided though, as the other half has stated that he only sees her as a sister and promised that he will try his best to love her as a woman. Despite his promise, so far, he's still only thinking of her just as a little sister.
- Playing with Fire: Inferno magic.
- Phlebotinum Rebel: She was created to kill Tatsuya if he ever threatened the world. In accordance with Murphy's Law, she came to sympathize with him over her creators and it is unlikely that she will want to uphold her duty.
- Power Incontinence: When she gets emotional things around her tend to get frozen. Explained in the novels in that Miyuki is using 50% of her power to suppress Tatsuya's magic. The moment she releases the seal, she gains full control of her magic.
- Protectorate: Tatsuya's duty is to protect her.
- Rage Against the Reflection: Her upcoming Arranged Marriage forces her to mentally confront problems that she would really rather not.
- Raven Hair, Ivory Skin: She is black-haired and pale-skinned, and everyone calls her the most attractive of all the girls.
- Rescue Romance: Subverted. She says that she fell in love with Tatsuya when he saved her life at Okinawa, but the prequel shows she was interested in him days before that.
- Role Reprisal: Was played by Saori Hayami in the audio drama CD.
- Sadistic Choice: In the Reminscence arc, learning about what her family did to Tatsuya forced her to make one. She could break from the people who had never shown her anything but support and love (admittedly, highly conditional love), or she could ignore their Mind Rape of one of their own children. She chose to do the right thing, though even now being reminded of what she gave up drives her to tears.
- Satellite Character: Miyuki's character is mainly based on her relationship with Tatsuya. She actually invokes this though, because she feels she has to.
- Satellite Love Interest: Tatsuya in the literal sense is the meaning of her life, and marriage with him is her main goal. The appearance of everything else in her life depends only on him.
- Secret Identity: Must hide that she is a Yotsuba.
- Selective Obliviousness: She wants to believe that she isn't incestuous, but can't quite get there.
- Set Right What Once Went Wrong: As heiress of the Yotsuba, it is her duty to inherit and pacify the...problem...that Miya left behind.
- Sex Is Evil, and I Am Horny: The main reason she attacks Tatsuya in the first volume is because he either doesn't reciprocate her attraction to him or he does but hides it better than she does. So not only is she perverted, but she is alone in her perversion.
- Ship Tease: Considering her feelings for him, most of her moments with Tatsuya are this.
- The Sixth Ranger: Even though she spends more time with Tatsuya she qualifies by not being one of his classmates. Her two friends too.
- Single-Target Sexuality: Men do not interest her at all, unless it's her brother Tatsuya. She even feels a little squeamish towards them, although she is able to communicate with them.
- Single Woman Seeks Good Man: She favourably contrasts Tatsuya's gentleness and regard for her desires to the sexual harassment Honami forces on her.
- So Beautiful, It's a Curse: She is such a Dude Magnet that she can't go out without being approached by various persons.
- Shameless Fanservice Girl: The spinoff makes it explicit that she tries to tease Tatsuya by wearing sexier outfits at home.
- Suspiciously Specific Denial: In Reminiscence, past!Miyuki thinks to herself that she's not among the girls who admire Tatsuya's "kindness, [..] calmness, and gentle features". Her words.
- Spoiled Sweet: Because of her brother's status, Miyuki does not have to treat him well, yet she tries to devote her whole life to him, even though sometimes it takes quite strange forms...
- Stepford Smiler: Can don an archaic smile to hide her feelings.
- Strong Family Resemblance: As Tatsuya resembles his father, Miyuki is very similar to his mother and aunt, especially in youth. This somewhat contradicts the subsequently discovered facts that her beauty is the result of genetic interference, however, Maya said that they only "improve" existing genes.
- Third-Person Person: Whenever Miyuki talks with Tatsuya or is alone with him.
- Tsundere: Type B combined with Oblivious to Love by Tatsuya. Miyuki progresses as a tsundere with the development of history, becoming more pronounced example of such characters after the 16th volume, when her no longer needed to hide their feelings after her declaration of love and engagement with Tatsuya. So, as Tatsuya for obvious reasons, can not respond to her feelings, at least for the moment, Miyuki often have to show tsun-tsun at the other girls, who may be a potential love interest of her brother, especially Honoka or Mayumi.
- Tomato in the Mirror: Miyuki accepted early on in her childhood that Guardians are human beings who deserve rights, which is convenient given that she's also an artificial creation.
- Tranquil Fury: Even better at it than her brother. And she is noted to be very scary when in this state. Obviously, it is because of her feelings for Tatsuya, which she developed since Tatsuya saved her from dying after being shot during the Defensive Battle in Okinawa which is the only time she was dying, losing body parts, being in a coma and everything else, and those feelings for her brother cause her to be angry or emotional whenever she is ogled by other guys or when other girls get close to Tatsuya.
- Troubling Unchildlike Behaviour: She knew a fatal spell and deliberately used it on an enemy during the Okinawa incident.
- Virgin Sacrifice: As long as she is alive, Tatsuya is incentivized to protect the Yotsuba (because their deaths would sadden her). The Yotsuba created her to serve this purpose.
- Warhawk: She does not see anything wrong with martially forcing people to do (what she thinks is) the right thing. Coupled with her impatience, this means that she must often be restrained from 'solving' every conflict in her life with violence.
- What Measure Is a Non-Human?: Subverted. She thinks having an artificial body is awesome, especially since it makes her more badass than 90% of organic humans.
- White Sheep: She is one of the few Yotsuba who have a functioning conscience. Which isn't to say that she's a good person, but she has standards, like not hurting family and not hurting innocents.
- Wounded Gazelle Gambit: Tatsuya doesn't know that his sister does things like torture captives for information, and she desperately wants to keep it that way.
- Yamato Nadeshiko: She is the embodiment of this; a gentle lady with Raven Hair, Ivory Skin who wears her hair in a Hime Cut. Always graceful and polite, as well as devoted to her family (her brother in particular) and possessing a great deal of inner strength. As stated elsewhere in her sheet, her family bred her to fit this trope, and she is not as gentle as she initially appears.
- Yandere: (Down-)played for laughs; she isn't actually dangerous to her brother's many admirers, but a lot of people are scared of her.
Year: 1st (Volume 12~)
- Barrier Warrior: Her series specializes in creating heat-resistant barriers.
- Bodyguarding a Badass: As Miyuki's female guardian.
- Born into Slavery: Her technical parents sold their DNA to Yotsuba before she was born, and since that time she is actually a lifelong servant of this clan as genetically improved magicans from the Sakurai series.
- Blessed with Suck: As a genetically improved magician, she has incredible magical talent, beauty and physical strength that can match the best noble magicians in Japan, but because she was genetically improved, her life span was cut several times and she was doomed to be a "slave" for all of her short life.
- Combat Pragmatist: In volume 23, she stops Mari from interfering with Tatsuya's fight against Katsuto by pulling out a handgun against her.
- Deal with the Devil: She is deeply tempted by Minoru's offer to leave the Yotsuba and become a Parasite minion alongside him, but concludes that the Parasites are too big a risk to humanity.
- Designer Babies: It was artificially created within the Sakurai series as a genetically improved magician.
- Generation Xerox: Honami was Miya's guardian. Now she is occupying the same role for Miyuki, Miya's daughter.
- Heroic Sacrifice: She survives shielding Miyuki magically from a terrorist bomb, but drawing on that much magic that fast leaves her hospitalized.
- Hidden Depths: Inside, she does not approve of the engagement between Tatsui and Miyuki, since she knows that in reality they still remain a brother and sister. But she is silent about this, believing that as a servant she not only has no right to interfere, but even talk about it.
- The Gift: Her talent is comparable to the Saegusa twins despite not being from being from the Ten Master clans. Her barrier even rivals Phalanx.
- Ninja Maid: She is not only an excellent magician and fighter, she is also Miyuki's personal servant.
- Shipper on Deck: Ships Mayumi and Tatsuya as a solution for Izumi who wants Miyuki to become her Onee-sama.
- Strong Family Resemblance: It is implied that she looks like a younger version of her aunt Honami, because her technical mother was a twin sister of Honami.
- Super Soldier: As Designer Babies, she is an almost perfect soldier and guard.
- Third Wheel: Having to share a house with Tatsuya and Miyuki would be hard even if they weren't siblings.
- Training from Hell: As someone raised to be a Yotsuba guardian, Minami's training has been very harsh.
- Voiced by: Yumi Uchiyama
Year: 1st (Volume 1~11), 2nd (Volume 12~)
Class: E (Volume 1~11), F (Volume 12~)
- Action Girl: The biggest of the series.
- Belligerent Sexual Tension: Averted with Leo. They certainly have the set up for it, but nothing actually happens beyond arguing.
- Big Brother Worship: To Naotsugu.
- Clingy Jealous Girl: Towards her brother and his relationship with Mari. Can be seen during the fourth novel/episode 15 of the anime. Towards Tatsuya when he also helps Angelina and Mayumi hunt down the vampires in Volume 10. When confronted by Mizuki, it turns out that Erika's been waiting for him to make the first move.
- Curbstomp Battle: Mibu stood no chance against her, even when she used a real sword against her.
- Genki Girl: Very upbeat and cheerful, Erika is easily the most energetic of the group.
- Hidden Buxom: Like Miyuki, her school dress hides her fairly decent sized bust.
- Innocently Insensitive: Erika is glad that Tatsuya doesn't pity her like other people have. She doesn't know at this point about his 'condition'.
- Implausible Fencing Powers: Cutting a steel magic powered pole with what amounts to a "stick"? Yeah she definitely has this.
- The Lancer: Generally supports Tatsuya on whatever choices he makes.
- Male Gaze: Erika in bloomers.
- Mama Bear: She takes quickly to protecting Kokoa and is the most fierce advocate for rescuing her sisters.
- Master Swordsman: In terms of pure swordsmanship she seconds only to Naotsugu in all the Chiba clan.
- My Brother Is Off Limits: Clearly disapproves of her brother's relationship with Mari.
- Nice Hat: Wears one in episode 15.
- Not So Different: With Leo. Tatsuya thinks she is similar to Mayumi as well.
- Red Oni, Blue Oni: Red to Mizuki's and Mikihiko's Blue. She is Red to everyone.
- School Sport Uniform: She wears one during an early episode but since the series is set in the future, it is considered to be a severely outdated style not commonly worn anymore.
- Screw the Rules, I Have Connections!: Erika uses connections she has in the military to get herself and some of the other characters into the hotel where Tatsuya and the other First High students are staying for the competition. She also says she has a way of getting into the party that night as well despite not being invited as a competitor in the events. Then it turns out she and the others are working as the wait and kitchen staff.
- The Tease: Dressed up and worked at the Nine School Competition's dinner gathering as a maid, partly to get in yes, but mainly to tease people.
- Tomboyish Ponytail: Her favorite hairstyle.
Leonhart "Leo" Saijou
- Voiced by: Takuma Terashima
Year: 1st (Volume 1~11), 2nd (Volume 12~)
Class: E (Volume 1~11), F (Volume 12~)
- Accidental Pervert: Accidentally sees Erika naked.
- Belligerent Sexual Tension: Completely averted with Erika. They are always arguing but they have no romantic feelings for each other.
- Big Damn Heroes: Saved Mikihiko at the last moment in Monolith Code
- But Not Too Foreign: His father is half-Japanese and his mother is a quarter-Japanese.
- Celibate Hero: He is not interested in romance and girls in general. He prefers food.
- Fighter, Mage, Thief: In Monolith Code, as the fighter.
- Good Old Fisticuffs: His main fighting style.
- Large Ham: Watch shout "PANZEEEEEEEEEEER!" while driving straight through a bad guy's gate.
- Made of Iron: Can take a whole lot of physical punishment. He even survived being hit by a motorcycle once. This turns out to be Super Toughness in truth.
- Not So Different: Him and Erika.
- Power Fist: His CAD is shaped like one.
- Screaming Warrior: Likes to scream when fighting.
- Smarter Than You Look: People tends to assume he is a Dumb Muscle.
- Strong Family Resemblance: With his sister. Turns out they're descended from a line of artificially-enhanced, genetically-manipulated Magicians, Burg Folge, which may contribute to this.
- Super Soldier: He is the third generation of the Burg Folge, Fortress Series, explaining his insane durability.
- Voiced by: Satomi Sato
Class: ETatsuya's classmate. A brainy girl and a very helpful member of the team, both of which are two reasons for critics of the series praising her.
- Aura Vision/Magical Eye: She can see Pushions.
- Blind Without Them: Averted. She wears glasses to reduce her sight so that she won't be harmed by too many psions since her eyes are sensitive to a certain amount.
- Brutal Honesty: Shy but when she is decided to speak, she is cunningly straightforward.
- The Fashionista: Though not very big on this, she does sport different hairstyles and accessories like headbands and bumpits.
- Meganekko: Her glasses actually act as a power limiter for her eyes. Because she's smart, she knows when to take off her glasses.
- Properly Paranoid: After Mari's accident she decided to remove her glasses while watching the NSC despite Erika's recommendation to not do this since it's painful for her.Thanks to this, she noticed an abnormality with Kobayakawa's CAD which permitted Tatsuya to bust one of No Head Dragon's mole.
- Red Oni, Blue Oni: Blue to Erika's Red.
- Shipper on Deck: Ships Tatsuya and Erika, as well as Tatsuya and Miyuki(!).
- Voiced by: Atsushi Tamaru
Class: E (Volume 1~11), B (Volume 12~)Tatsuya's classmate, promoted to Course 1 when Magical Engineer Course was created at the start of the second year and some former Course 1 students transferred into that Course, causing vacancies. Erika's childhood friend.
- Accidental Pervert: Inadvertently groped Mizuki's breasts.
- The Ace: Mikihiko is renowed as a prodigy in his family. Excelling at Summon Magic.
- Affectionate Nickname: Erika calls him Miki, but see below.
- Almighty Janitor: Even before he became a Course 1 student in the 2nd year his skills were noted to be that of a Bloom.
- Broken Ace: After his accident. Then became The Ace again during the Nine Schools Competition
- Combat Hand Fan: Has a fan-shaped CAD.
- Childhood Friend: With Erika.
- Do Not Call Me "Paul": It's Mikihiko, not Miki. Although he realized that Resistance Is Futile once Lina insists on calling him that.
- Fighter, Mage, Thief: In Monolith Code, as the mage.
- Kungfu Wizard: Practices martial arts.
- The Lancer: Shares the role with Erika.
- Mr. Exposition: He is this when it comes to explaining stuff about SB (Spirit Body) Magic.
- Summon Magic: SB magic summons Spirits.
- Super Senses: Via Sense Tuning.
- Swiss-Army Superpower: Spirit Body magic is slower than modern magic, but is very useful and versatile.
- Took a Level in Badass
- Voiced by: Sora Amamiya
Year: 1st (Volume 1~11), 2nd (Volume 12~)
- Adaptation Dye-Job: Her eyes are purple in the anime.
- Childhood Friends: With Shizuku.
- The Cutie: Honoka is sweet, cute and innocent; contrasting the more serious and focused characters in school.
- Dogged Nice Girl: Her feelings for Tatsuya are unrequited but she still tries.
- Everyone Can See It: Her crush on Tatsuya. It's so obvious Tatsuya himself finally understood it.
- Flat Character: She has a crush on Tatsuya and is friends with Miyuki and Shizuku. That's all there is to know about her.
- Friendly Rivalry: With Miyuki and Shizuku.
- Hidden Buxom: In volume 3. The same is for Miyuki throughout the novels.
- I Just Want to Be Badass: Unlike Miyuki and Erika she lacks combat skills and try to do her best to be useful in other areas.
- In the Blood: Undying Loyalty and submissiveness to their loved ones is a trait of the Elements.
- Light 'em Up: She specializes in manipulating light.
- Love at First Sight: To Tatsuya upon seeing his magic for the first time.
- Love Confession: To Tatsuya, she got rejected.
- Master of Illusion: Via light manipulation.
- Nice Girl: She's very supportive and friendly towards her friends, and is one of the few students that do no discriminate between course 1 and course 2 students.
- Smitten Teenage Girl: She develops a huge crush on Tatsuya without knowing anything about him except that he's handsome and competent. While mostly portrayed positively, she does wonder if she even has a chance with him.
- Tender Tears: After her victory in Battle Board.
- Those Two Girls: She is always seen together with Shizuku.
- Voiced by: Yuiko Tatsumi
Year: 1st (Volume 1~11), 2nd (Volume 12~)
- A-Cup Angst: In episode 10, Honoka is about to be groped by Eimi in the bath. She calls out to Shizuku for help, and the latter responds by simply walking out of the bath. When asked why she's leaving, Shizuku simply pats her chest, then mentions Honoka having bigger breasts than her.
- Emotionless Girl: Acts more stoic that even Tatsuya! However, she does have feelings and Erika many times points out moments where Shizuku wasn't calm, good-tempered or thinking.
- The Fashionista: Shizuku has worn different dresses and winter clothes with gloves throughout the series.
- Friendly Rivalry: With Honoka and Miyuki.
- Manga Effects: Though there is no single expression she uses more than once in this category, Shizuku has made facial iconography that exagerrated her whole face.
- Shipper on Deck: Ships Tatsuya and Honoka, before the events of the 20th volume, where she is already open requests Tatsuya refuse her friend.
- Spoiled Sweet: By her father.
- Those Two Girls: She is always seen together with Honoka.
President Mayumi Saegusa
- Voiced by: Kana Hanazawa
Year: 3rd (Volume 1~11), Magic University (Volume 12~)
- A Day in the Limelight: In The Ojou-sama's Magnificent Day Off.
- A Mother to Her Men: Mayumi cares about the welfare men who positioned as her potential love interest. In particular, she helps promote Tatsuya and supports the usually taciturn and quiet Katsuto.
- Batman Gambit: After a demoralizing incident during the NSC, she orders the team's technician, Tatsuya, to go into their tent and comfort them. Tatsuya doesn't know how to do that, and he's scared that he might accidentally make them feel worse, so in the end he decides to just work as normal inside the tent and not mention the incident at all. This is exactly what Mayumi intended, because seeing someone who (they thought) was calm made the team calm down.
- Beware the Nice Ones: She doesn't like violence, but is fully capable of fighting if the need arises.
- Big Good: Of First High. As student council president she is the diplomatic face of the student government's Power Trio that calms people down and keeps everything from breaking out into violence. She is also highly sympathetic to the plight of the Course 2 students and tries to break the discriminatory attitude against them in the Course 1 students.
- Cool Big Sis: she looks at the younger students of the school of magic as her younger brothers and sisters, helping them with advice and being a personal example for them. Moreover, being a foil to Miyuki and having two younger twin sisters she plays it trope directly.
- Flawless Victory: Her victory in Speed Shooting was perfect.
- Foil: to Miyuki. While both of them may be called Yamato Nadeshiko, Mayumi has a more calmed personality while secretly has her cheerful side, tending towards ojou-sama. In addition, she tells Tatsya how he is like a younger brother to her, what making this comparison even more ironic, considering her feelings for him. It evolves at the same time as romantic plotline progresses in the series, when Mayumi slowly realizes her feelings for Tatsuya, but in contrast to Miyuki, trying to develop their relations in a more calm way.
- The Gadfly: Enjoys teasing Tatsuya about his love life, and for the most part, he goes along with it.
- The Gift: Considered as a genius born once in every ten years at remote precision Magic. And is a direct descendant of the Ten Master Clans.
- Height Angst: She has a size complex and reminding her of her size is her Berserk Button.
- Huge Guy, Tiny Girl: With Tatsuya and especially Katsuto.
- Improbable Aiming Skills: She is not in the top 10 in long-range precision shooting for nothing.
- Spread Shot: Of the Spray Burst variety.
- In-Series Nickname: Elfin Sniper. She doesn't like it because of her size complex.
- Leeroy Jenkins: In the Isolation arc. Yes, it was a tense moment, but how could attacking a guy whose psychotically protective sister is standing right next to you be a good idea?
- Massive Numbered Siblings: She has two older paternal half-brothers and two younger sisters, making her the middle child in the Saegusa family.
- More Dakka: With Ice pellets.
- Nice Hat: Wore one for the trip before the NSC.
- The Nicknamer: She loves to give her friends silly nicknames.
- One-Woman Army: She beat a multitude of attackers with heavy weaponry and magicians by herself in less than 5 minutes.
- Passing the Torch: After Mayumi's term ends, Azusa Nakajou succeeds her as the student council president
- Red Baron: The Magic Shooter
- Secret Keeper: She realizes in Volume 5 that Tatsuya is lying about his heritage, but decides to trust him anyway.
- Student Council President: She held this position during the first year of the Shiba siblings.
- Suspiciously Specific Denial: When confronted by Mari about having a crush on "that guy" Mayumi immediately knows that she's talking about Tatsuya, not Katsuto. She's completely flustered while ardently declaring that she can't possibly be in love with Tatsuya. Taken Up to Eleven. She insists that she just sees him as a younger brother... when he has a brocon younger sister. The Irony. Mari collapses at the table due to her completely unconvincing act.
- Love Interest: she is often regarded as the second potential love interest for Tatsuya after Miyuki.
- Troll: She and Tatsuya love to amiably make fun of each other.
- Unwitting Muggle Friend: She is one of the few magicians who socializes with non-magicians, going out to clubs and such.
- Womanchild: Downplayed but she acts childish sometimes, usually when she's with Tatsuya. Contrasts with Tatsuya who is very mature.
- Voiced by: Marina Inoue
Year: 3rd (Volume 1~11), Defense University (Volume 12~)
- Battle Couple/Official Couple: With Chiba Naotsugu.
- Casual Kink: She says that she doesn't mind her boyfriend not acting like a gentleman...then she gets very embarrassed and refuses to speak.
- Even the Girls Want Her: She is more popular with females at school.
- Master Swordsman: Excels at swordsmanship but inferior to swordsmen like Naotsugu and Erika.
- Mistaken for Gay: Kirihara believed her and Kanon were lesbians.
- Never Bring A Knife To A Gunfight:In volume 23, she was stopped by Minami just by pulling out a handgun against her.
- Smug Super: She likes to remind people that she's one of the top fighters of 1st High.
- The Strategist: Not as good as Tatsuya though.
- Those Two Girls: To an extent with Mayumi.
- Tomboy and Girly Girl: The Tomboy to Mayumi's Girly Girl.
- Tsundere: Towards Mayumi, sometimes.
- Voiced by: Junichi Suwabe
Year: 3rd (Volume 1~11), Magic University (Volume 12~)
- Anti-Magic: Phalanx has Counter Magic properties.
- An Arm and a Leg: Has this after being subjected to Baryon Lance during his battle against Tatsuya in volume 23, shocking him, Mayumi, Mari and Tsukasa's forces. Fortunately, Tatsuya restores it after he surrenders.
- Attack Reflector: The Reflector barrier. It creates a forcefield which reverses motion vectors.
- Barrier Warrior: Specializes in magic barriers.
- Curbstomp Battle: Almost all his fights qualify.
- Epic Battle Boredom: Remained untouchable while crushing everything with his barriers in Volume 7.
- Foe-Tossing Charge: He won the final of Monolith Code by beating his opponents this way.
- Foil: To Tatsuya. Even their powers contrast each other.
- Huge Guy, Tiny Girl: Mayumi is very small and he is a giant.
- I Want My Beloved to Be Happy: He readily accepts that Mayumi isn't interested in him and tries to help her escape their Arranged Marriage.
- The Juggernaut: He is unstoppable with his barriers on.
- Lightning Bruiser: Strong, with the best defensive magic and proficient in high speed Move-Type Magic.
- My Kung-Fu Is Stronger Than Yours: How Tatsuya interpreted his easy victory in Monolith Code.
- Red Baron: The Iron Wall
- The Quiet One: Doesn't talk a lot but is very charismatic.
- Shipper on Deck: Shipped Tatsuya and Mayumi, also Tatsuya with Mayumi's sisters.
- Spam Attack: Offensively, Phalanx is used to annihilate the enemies thanks to the rapid succession of barriers.
- Superpower Lottery: Phalanx is the best magical defense existing, each barrier is replaced as soon as one is destroyed. He has many other types of strong barriers as well.
- Younger Than He Looks: Katsuto is only two years older than Tatsuya, although because of his developed masculature and a manly face, he looks much older.
- Voiced by: Takashi Oohara
Year: 1st (Volume 1~11), 2nd (Volume 12~)
- A Day in the Limelight: In The Honour Student's Supplementary Lesson.
- Jerkass: He's a jerk to Tatsuya and his friends for being Class 2 students.
- Quick Draw: What his family is famous for.
- Voiced by: Mai Nakahara
Year: 3st (Volume 1~11), Magic University (Volume 12~)
- The Stoic: She hardly loses her composure in the face of adversity. She can compare to Tatsuya and Shizuku in that regard.
- Team Mom: Mayumi might be the student council president, but Suzune is easily the most normal person in the student council.
- Voiced by: Saki Ogasawara
Year: 2st(Volume 1~11), 3rd (Volume 12~)
- Adorkable: She is easy to frighten and also geeks out in the face of interesting technology.
- Animal Motifs: Often compared to a squirrel.
- Fangirl: Big fan of Taurus Silver's products. Tatsuya uses one to bribe her into becoming the next Student Council President.
- Magic Staff: Azusa can conjure one in order to cast Azusayumi.
- In the anime, this is changed from a staff to an Energy Bow.
- Student Council President: Successor to Mayumi when her term ended.
- You Are in Command Now: She becomes the leader of the Student Council after Mayumi's term ends.
Vice President Gyoubushoujo Hanzou Hattori
- Voiced by: Ryohei Kimura
Year: 2st (Volume 1~11), 3nd (Volume 12~)
- An Ice Person: Dry Blizzard.
- Arrogant Kung-Fu Guy: Zig-Zagged. He became like this after becoming a top student at First High but his loss against Tatsuya made him more humble.
- A Taste of Defeat: His loss against Tatsuya was his first one.
- Butt-Monkey: Mayumi constantly teases him when they are together.
- Jack-of-All-Stats: He has no particular talents but is one of the strongest students in First High.
- Named After Somebody Famous: Hattori Hanzo.
- Number Two: He serves as Mayumi's second-in-command.
- Shock and Awe: Slithering Sanders.
- Voiced by: Tomokazu Sugita
Year: 2st (Volume 1~11), 3nd (Volume 12~)
- Voiced by: Haruka Tomatsu
Year: 2st (Volume 1~11), 3nd (Volume 12~)
- Brainwashed and Crazy: By Blanche, for most of the Introduction arc.
- Knife Nut: Excels at knife throwing.
- Loving a Shadow: She says that she loved Tatsuya, but what she really loved was his confidence, especially since she lacked it so much. His real self scared her.
- More Than Mind Control: The Course 1 students' bullying is real and enrages all of their victims, but Sayaka had Fake Memories implanted in her in addition to the real ones. They're what convinced her that all Course 1 students were cruel and that there was no other way to stop the bullying other than violence.
- Official Couple: She eventually gets together with Takeaki.
- Unwitting Pawn: Was brainwashed by Blanche.
- Voiced by: Gou Shinomiya
Year: 2st (Volume 1~11), 3nd (Volume 12~)
- The Ace: At martial arts.
- Blow You Away/Elemental Armor: Air Armor.
- Fights Like a Normal: Can use magic but it's stated he can beat opponents without using it.
Year: 1st (Volume 1~11), 2nd (Volume 12~)
Class: B (Volume 1~11), E (Volume 12~)
- Anti-Magic: Masters a contact-type Gram Demolition.
- Artistic License Martial Arts: Justified. He is able to make impossible moves thanks to Self Marionette.
- Close-Range Combatant: He can't use distance magic but is excellent at CQC.
- Cursed with Awesome: He is born with a defect making him unable to use magic at long distance but thanks to this he has access to the rare and powerful Counter Magic Gram Demolition which is a fearsome weapon coupled with his martial skills at close range.
- In-Series Nickname/My Hero Zero: Range-Zero.
- People Puppets: To himself with his Self Marionette.
- Voiced by: Soma Saito
Year: 2st(Volume 1~11), 3rd (Volume 12~)
- Bishōnen/Dude Looks Like a Lady: Frequently lampshaded.
- Nice Guy: Seriously, he doesn't have a mean bone in his body.
- Savvy Guy, Energetic Girl: With Kanon.
- Voiced by: Saori Onishi
- Action Girl: One of the top fighters at First High.
- Adaptation Dye-Job: Her hair color is purple in the anime.
- Battle Couple: She fights alongside Kei.
- Clingy Jealous Girl: Gets annoyed everytime Kei is complimented or is acting nice to other girls.
- Mistaken for Gay: Kirihara believed her and Mari were lesbians.
- Person of Mass Destruction: Mine Genesis qualifies. She must be wary of her surroundings when she use it for that reason.
- V-Sign: In the anime after her victory in Ice Pillars Break.
Eimi Amelia Goldie Akechi
- Voiced by: Asuka Nishi
Year: 1st (Volume 1~11), 2nd (Volume 12~)
- A Day in the Limelight: In Amelia In Wonderland.
- Adaptational Attractiveness: In her original design, Eimi had much shorter hair and lacked her unique bow and braid. She later had her appearance changed for the anime, which carried over into the manga, despite the fact that she had already made an appearance with her old hair style.
- Genki Girl: The most cheerful character of the series.
- In-Series Nickname: Emmy.
- But Not Too Foreign: Quarter British.
- Voiced by: Yuka Saito
Year: 1st (Volume 1~11), 2nd (Volume 12~)
- Alliterative Name: Subaru Satomi
- The Generic Girl: Doesn't have any unique attributes to distinguish her from the other Class 1 girls.
- MegaNekko: Never seen without her glasses.
- Fangirl: Of Miyuki, from the very moment they met.
- Break the Haughty: His fight against Tomitsuka and Tomitsuka's fight against Tatsuya was this to him.
- Flechette Storm/Paper Master: Million Edge. He is able to throw 1,036,800 paper blades.
- Voiced by: Sakura Tange
A school counselor. Part time agent of Public Safety.
YanagisawaA school counselor.
- Voiced by: Nao Touyama
- Voiced by: Yoshitsugu Matsuoka
A first year at third high, son of the Ichijou of the Ten Great Clans, known for participating in real combat. Has a crush on Miyuki.
- Anti-Magic/Attack Reflector: Armor of Interference can do both.
- A Taste of Defeat: Lost for the first time against Tatsuya.
- Bishōnen: The audience gets to quickly see his body from his shower scene in episode 7. He's an athletic adolescent male with slender glabrous legs, a compact waist, and a toned but lithe upper body with a soft boyish face. Definitely a bishonen.
- Brains and Brawn: He is the brawn, Shinkurou is the brains.
- Blood-Splattered Warrior: Fits him to a T. His Red Baron is a reference to this trope.
- Chick Magnet: Masaki is handsome enough to be one. Kichijouji muses on the fact the first time Masaki showed interest in Miyuki.
- Child Soldier: Masaki pushed back the NSU invasion in Sado Island during the time when Tatsuya was destroying the invading GAA troops in Okinawa after Miyuki was nearly killed.
- Drama-Preserving Handicap: As an ability that can literally One-Hit Kill any human, Rupture is naturally banned from use in Monolith Code, rendering Ichijo merely a really strong opponent instead of an unstoppable killing machine.
- Earn Your Title: Earned the title of Crimson Prince after a battle where he was bathed in blood.
- Having a Blast: Can do this asily with Rupture as long as there is some liquid within his target.
- Heterosexual Life-Partners: With George. Even when he's naked bathing George is no more than 5 feet from him.
- Hopeless Suitor: Miyuki is too large Brocon, in addition to which she is already engaged to her brother, so Masaki just no chance. Moreover, because of the peculiarities of her with Tatsuya birth, her marriage with someone else simply impossible, even if she wanted it. However, she does not feel animosity towards him, so Masaki still trying to win her love.
- The Juggernaut: Defeated all the students of Eighth High while maintaining his Armor of Interference. His performance was noted to be similar to Katsuto's style.
- Love at First Sight: After seeing Miyuki. He is not the first one.
- Love Makes You Stupid: He started acting bizarrely after encountering Miyuki.
- Mistaken for Gay: By his little sister, as she thinks that he spends too much time with George.
- Mr. Fanservice: The anime added a scene with him taking a shower.
- Naked on Arrival: He debuted in the anime with a shower scene detailing his lithe upper body.
- Oh, Crap!: The look on Masaki's face after the use of excessive force against Tatsuya in Monolith Code. Tatsuya then exploited that opening to knock Masaki out of the competition.
- One-Man Army: His power was evaluated to be that of an entire battalion by Kazama. He killed a lot of enemies at 13 and at Yokohama too.
- Person of Mass Destruction: In vol. 27, Masaki is now recognized as the 14th apostle and the 2nd Japan registered SCM through the efforts of Tatsuya(who provided the software) and Kichijouji(who provided the hardware).
- Playing with Fire : His Rupture spell makes people's bodies explode by vaporizing their blood.
- Privileged Rival/Unknown Rival: A bit of both, he is a Foil to Tatsuya and while Tatsuya acknowledges his strength and accepted his challenge, the fact that he is highly competitive in contrast to Tatsuya makes their rivalry look one-sided most of the time, especially after the NSC.
- Red Baron: Crimson Prince, after he returned from a battle covered in his enemies' blood.
- Self-Imposed Challenge: Masaki decided- entirely spontaneously- that he couldn't confess to Miyuki until he defeated her brother. His pride as a man demands it.Kichijouji did not say that he thought [Miyuki] would not care about that.
- Spirited Competitor: Very competitive.
- Superpower Lottery: As long as you are made of flesh and blood, Rupture is a One-Hit Kill. It is also considered a Game-Breaker in Monolith Code.
- Tempting Fate: He confidently smirks as George comments that he has no equal while getting out of the shower. During the final match in the Monolith Code tournament the Crimson Prince gets his butt throughly spanked by Tatsuya and is calmly knocked out in one hit. His team loses 3-0.
- The Unfettered: An unintentional example. When Tatsuya attacks him in Monolith Code, Masaki panics and illegally strikes him with an Air Bullet. Fortunately, Tatsuya can regenerate the damage.
- Willfully Weak: He had to reduce the power of his attacks during the Nine Schools Competition to not infringe the rules.
- Voiced by: Ayumu Murase
Masaki's classmate and best friend. Discovered the Cardinal Code at age 13.
- A Taste of Defeat: Felt beaten by Tatsuya strategically after his school's loss at Monolith Code.
- Affectionate Nickname: Masaki calls him Jouji.
- Best Friends-in-Law: Averted. Due to a misunderstanding, Masaki thinks that Jouji is interested in his sister.
- Brains and Brawn: The brains to Masaki's brawn.
- Break the Haughty: He was confident he was the best strategist of the Nine Schools Competition but Tatsuya proved to be better than him.
- Butt-Monkey: The poor boy is often accused of pedophilia or homosexuality, depending on the agenda of the person doing the accusing.
- Color Motif: Canonically, his nickname of 'Cardinal' refers to his discovery of a Cardinal Code, but it also fits his eyes, which are deep red like a cardinal bird's feathers.
- Heterosexual Life-Partners: He and Masaki are rarely seen apart, and have already decided to spend the rest of their lives working together.Akane: (to Masaki) Im not letting you have Shinkurou-kun all to yourself!
- In-Series Nickname: Cardinal George.
- Merlin and Nimue: He tutors Akane.
- Mistaken for Gay: Such as when Masaki refers to himself and George as a "pair"- in the athletic sense, not the romantic one- and Akane overhears.
- Spirited Competitor: Just like Masaki.
- Undying Loyalty: To the Ichijous, because their sponsorship meant he didn't have to go into an orphanage after his parents were killed.
Harunobu KazamaThe leader of the 101. An Ancient Magic user known as Daitengu, he despises the Ten Master Clans System.
- Voiced by: Toru Okawa
Shigeru SanadaA captain of the 101; more of an engineer than a fighter.
- Voiced by: Tarusuke Shingaki
- Voiced by:
- Curbstomp: Beat a Generator in no time but Kyouko is the one who gave the final blow.
- Gravity Master: Thanks to his Thousand Tatami magic.
- One-Man Army: As many others in the Yokohama arc.
- Vitriolic Best Buds: With Sanada.
- Voiced by: Shizuka Ito
- Red Baron: The Electron Sorceress.
- Voiced by: Teruyuki Tanzawa
- Mad Scientist: He wants to experiment on Tatsuya and doesn't hide it.
See Third High School
- Aesop Amnesia: They were horrified by infant Tatsuya's destructive potential...and then they thought 'why don't we try to use it against our enemies?'. So they enslaved him, made him into a ruthless killing machine, etc, and then several years later someone else frees Tatsuya and he is not pleased with the family who made his life a living hell.
- Be Careful What You Wish For: Like all magician groups, the Yotsuba use eugenic techniques and genetic engineering to ensure their offspring have increasingly strong magic. Unfortunately, they were the first group to experience the logical consequence of such techniques.
- Big, Screwed-Up Family: The current head of the clan wants to destroy the world through engagement between her nephews, for which she manipulates incestuous feelings her younger niece to her own brother. In addition, the last head has arranged a bloody vendetta against a secret organization that kidnapped his daughter, and as a result of this, the clan killed 4,000 people while losing only 18 of its own.
- Black and Grey Morality: The morally worst threat is Maya, who wants to destroy everything. A little up from her are the majority of the clan, who enable slavery and child abuse because it's convenient. And up from them are the protagonists, who are vaguely interested in preventing the above atrocities. But all of these characters are terrible in their own ways.
- Black Site: The 4th institute and any Yotsuba residencies. Also, given they're specialized in black ops, government agencies gives them access to their own black sites.
- Brainwashing for the Greater Good: They say this, but they jumped on the chance to use Tatsuya after his Mind Rape, so...
- Dark Secret: Factions are supposed to openly declare the existence of any strategic-class magicians within them, but the Yotsuba didn't do this when Tatsuya was born.
- Did You Just Punch Out Cthulhu?: It took a few years of preparation, but the Yotsuba managed to mutilate a Physical God. Mutilated it so hard that even a decade later he is still essentially their attack dog.
- The Dreaded: Even USNA, the strongest country in the world, fears them.
- Epic Fail: Every attempt the Yotsuba make to fix their mistakes only makes things worse, because a) they refuse to acknowledge that they were in the wrong in any way, and b) those attempts always involve 'fucking with the natural order again, in the hope that this time that will work'. Special mention goes to the FaceHeel Turn of Miyuki, who was literally created for the sole purpose of supporting the family's interests.
- Evil Cannot Comprehend Good: Miya readily tells a thirteen-year-old child that the Yotsuba Mind Raped Tatsuya, because she genuinely doesn't see (or doesn't care about) the inhumanity of such an act.
- She is quite literally incapable of this, due to her limited emotions, after suffering backlash from her Mental Design Interference on Tatsuya's emotions, making her lose a portion of the potency. Also, she has a unique view on the mental structure of the brain, as a required secondary power to her Mental Design Interference, so she might not see anything wrong with this either way.
- Evil Counterpart: To the Yoshida family, who work alongside eldritch spirits beyond human comprehension instead of enslaving them.
- Freudian Excuse: Several decades before the start of the series, the Yotsuba's then-heiress and figurehead was kidnapped and tortured. Their fear and shame twisted them into becoming even more paranoid then they had been before.
- Gone Horribly Right: Tatsuya's power stems from the Yotsuba's wishes for a savior, and Maya's wishes for a destroyer after the incident at Dahan.
- In the Blood: Ruthlessness. Not all Yotsuba are evil, but they only care for their allies and subjects. Anyone else is expendable.
- A Lesson Learned Too Well: They made it so Tatsuya would (probably) not destroy the world because of emotional extremes. However, he may now destroy the world because he is sociopathic.
- Names to Run Away from Really Fast: Lampshaded by Miyuki when she planned to use her identity as a Yotsuba when a politician was bothering her. Also by Volume 17, only Erika and Leo amongst his closest friends never feared Tatsuya when his identity as Yotsuba was revealed.
- Personality Powers: All their magics reflect some part of entropy: ice, darkness, amputation of memories or emotions, Anti-Magic...
- Power Equals Rarity: Its resources are channelled into strange, unprecedented biological projects instead of expanding the clan through more typical ways.
- Red Baron: The Untouchables.
- The Spartan Way: Yotsuba magicians and their guardians are trained this way, making their combat prowess levels above any other clans.
- Token Evil Teammate: They are the Clan that specializes in black ops and information control note ; not coincidentally, their bloodline grants the ability to Mind Rape. Although given their increased attempts to dominate Japan's magicians, they may not be a 'teammate' anymore...
- A Tragedy of Impulsiveness: They panicked when they realized what was gestating in Miya's womb, so they created a second, slightly less apocalyptically-powerful child to follow the first one around and control it. Unfortunately, no one is around to control that one.
- Vetinari Job Security: The Yotsuba can singlehandedly turn the tide of whatever conflict they join, and they are not shy about milking this fact for all it's worth.
- Quality over Quantity: They lacked numbers compared to the other clans yet their combat prowess makes it up for it. Taken Up to Eleven when they even have the God of Destruction.
- Wardens Are Evil: A side story reveals that one of the trainings for Yotsuba magicians was to guard a volcanic island prison where very dangerous individuals are held.
- Voiced by: Chiwa Saito
- Always Identical Twins: She and her oldest twin-sister Miya
- Anti-Villain: Although she is able to manipulate the feelings and life of their relatives for the sake of realization of their cruel and insidious plans, she does so not because of the natural malice, but because of the heavy and tragic past, completely broke her life and deprived of her future. Moreover, it seems to be sympathetic to the situation of Tatsuya and promises to put up with her defeat, if she loses.
- Born Winner: Is from the second lineage of the Yotsuba
- Driven to Madness: Her abduction and inflicted harm caused to what she wants to destroy the world with Tatsuya power.
- The Chessmaster: Maya is famous for her cunning and complex plans, in particular her most famous plan was developed more than 15 years. For example, her is quite easy managed use Miyuki's love for his brother and Tatsuya affection for her, to put him in an impossible position and announce engagement between Tatsuya and his sister.
- Older Than They Look: So, as Maya is the twin sister of Shiba siblings's mother, she also looks 10-15 years younger than she really is.
- Orcus on His Throne: And using Skype. Maya is the main antagonist of the series, but she doesn't especially care what the protagonists do as long as they're still under her thumb.
- Evil Counterpart: Many of her traits are Tatsuya's taken to truly villainous extremes- playful teasing becomes sadistic manipulation of people's lives, bitterness towards abusers becomes bitterness towards everyone, withholding information out of distrust instead of misguided independence, etc.
- Evil Matriarch: Subverted. She is not the real mother of Tatsuya and Miyuki, but being their aunt and Tatsuya's foster mother, she plays this role increasingly with every new arc. In particular, she deliberately organizes his engagement with his own sister to make Tatsuya a prisoner of the clan and turn them both into a target for other clans and foreign powers. She even hopes that they do not fall in love with each other, just because otherwise there will be no conflict in their Arranged Marriage .
- Perfectly Arranged Marriage: With Koichi, before her abduction.
- Family Relationship Switcheroo: In the 16th volume, she falsely announces that Tatsuya is her son.
- For the Evulz: It seems that she enjoys provoking people. In particular, she specifically tells Miyuki that the Saegusa clan is trying to pairing Tatsuya with Mayumi so Miyuki will become jealous.
- Rape as Drama: She lost the opportunity to give birth after experiments during her abduction at the age of 12. This also caused the Saegusa family to abandon the marriage of their heir with her.
- Red Baron: The Devil of the Far East, Queen of Night.
- Sibling Rivalry: In her own words, since she actually "stole" her sister's son and had sinister plans for his future, Miya was in a state of cold war with her.
- Superpower Lottery: Meteor Stream is one of the strongest magics.
- The Last of These Is Not Like the Others: In comparison to the other clan heads, she wears casual, frilly clothing even while conducting official business. This is less because she doesn't take politics seriously than because, when you are Maya Yotsuba, you have earned the right to wear whatever the hell you want.
- Wicked Stepmother: She states that Tatsuya is her son and adopts his, but in fact it is made to Miyuki was able to marry him as his "cousin". Moreover, thanks to this she deliberately puts them both in a very risky situation in order to provoke the end of the world.
- Unblockable Attack: Meteor Stream is unblockable due to how it works. Doesn't mean it can't be broken.
- Always Identical Twins: She and her younger twin-sister Maya
- Deceased Parents Are the Best: Averted. At least for Tatsuya.
- Older Than They Look: She was about 30 years old when she gave birth to Tatsuya and Miyuki, and despite the fact that at the time of the described events she is already in the middle of the 40th, she still looks for 25-30 years.
- Parental Neglect: Doesn't care about Tatsuya at all.
- Mama Bear: She sincerely loves and cares about her daughter, Miyuki, despite the fact that she was born artificially from her egg cell and subsequently heavily modified. It is assumed that she gave Miyuki all that parental love that she could not give to Tatsuya. At the same time, Maya mentions that Miya was sincerely proud of her son.
- Red Baron: Mistress of Lethe
- Sibling Rivalry: For the rest of her life she was in a state of "cold war" with her younger sister, which was caused both by severe changes in the personality of the latter, and by suspicions that Maya has some hidden plans about her son.
- Strong Family Resemblance: Miyuki very much reminds her of her youth, especially her hair and face profile.
- Blow You Away/Weaponized Teleportation: Mock Teleportation is a mix of both.
- Kissing Cousins: She is unrequited in love with Tatsuya, who is her second cousin.
- Half Identical Twin: With her oldest brother Fumiya and with him she plays twin's tropes like a Twin Banter or Fearful Symmetry
- Brother-Sister Team \ Tag Team Twins: With Fumiya.
- Ojou : She is a fairly typical example of this trope, in particular, Ayako always looks elegant and have western-style hairstyle.
- Unknown Rival: To Miyuki.
- Tender Tears: Has this when Miyuki was engaged to Tatsuya.
- Tsundere: Has shades of this in Volume 8. She does have feelings for Tatsuya and cried when she heard that Tatsuya and Miyuki is betrothed to each other.
- Ambiguously Gay/Mistaken for Gay; Played for Laughs but the narration made it clear that he is not gay.
- Dude Looks Like a Lady: He still looks very young and feminine because of his twin sister, with the result that adults loved to dress him as a girl when he was a child. In the 18th volume Tatsuya even notes that, together with Ayako, they are like two cute younger sisters.
- Half Identical Twin: With his youngest sister Ayako and with her he plays twin's tropes like a Twin Banter or Fearful Symmetry
- A Child Shall Lead Them: Leads the Kuroba despite his young age.
- Hero-Worshipper: Is a fanboy for Tatsuya.
- Luminescent Blush: After being complimented by Tatsuya.
- Spoiled Sweet: Treats Tatsuya and Miyuki the same despite Tatsuya's status of guardian.
- Took a Level in Badass: Was presented as a Cheerful Child in the Reminiscence arc. Now he is a competent fighter and a great leader.
- Wholesome Crossdresser: Much to his displeasure.
- Voiced by: Takehito Koyasu
- Happily Married: He finally married Sayuri after Miya's death.
- Strong Family Resemblance: Tatsuya resembles him.
- Your Cheating Heart: Even after his marriage with Miya, his ex-girlfriend was still his lover.
- Voiced by: Megumi Toyoguchi
- Plagiarism in Fiction: She demands that Tatsuya hand over everything he creates to her.
Honami SakuraiMiya's guardian.
- A Good Way to Die: Was satisfied by her death because it was the result of actions conducted by her own will.
- Barrier Warrior: The specialty of the Sakura series.
- Cool Big Sis: She was more of a parent to Tatsuya than his biological ones.
- Tyke-Bomb: Lampshaded when she died.
Genzou YotsubaMiya and Maya's father.
- Making a Splash: Abyss, a strategic-class magic that is highly effective against fleets.
- Older Than They Look: Due to her physical weakness (a side-effect of the demands of her magic), her physical development is very slight.
- Person of Mass Destruction: Is a strategic-class magician.
- Arranged Marriage: He was engaged to Mayumi, while their parents have not realized that they are not interested in each other
- Unknown Rival: Seems to be one to Katsuto.
- Accomplice by Inaction: He learns about the Parasite Doll tests but does nothing to stop it because their 'only' victims will be first-year students.
- Perfectly Arranged Marriage: Was Maya's boyfriend and fiancé but the Saegusa clan broke off the engagement due to Maya's loss of biological reproduction capability, as well as her loss of emotional attachment to her fiance.
Mayumi, Kasumi and Izumi Saegusa
See First High School
- Inseries Nickname: The Patriarch.
- The Patriarch: It's even his nickname.
- Red Baron: The Sly Warlock.
- World's Strongest Man: He was once the world's strongest magician.
Makoto KudouRetsu's eldest son and current head of the clan.
- I Just Want to Be Special: Kinda. As a magician of the Ten Master Clans he is born with amazing magic power it's just that his magic power is average by their standards. He has an inferiority complex because his talent doesn't compare to his father's.
Minoru KudouThe youngest grandson of Retsu, he is born from Makoto and his younger sister. His magic power is one of the most powerful of his generation but he can't use it constantly due to his physical frailty.
- Augmented Magician: Makoto believed children born from him and his sister would be far more talented. He was right but Minoru has serious health problems.
- Chick Magnet: As Miyuki, his appearance at once causes interest in him on the part of many women, and even the some guys.
- Deal with the Devil: According to untranslated volumes, Minoru accepts Parasites into his body because they will strengthen him.
- Designer baby He is born from the genes of Makoto and his sister, without sexual intercourse.
- Ill Boy: He is sick and spends a lot of time bedridden, unable to show his great magic power. It is either because of an error in the modification process or because of inbreeding.
- Royal Inbreeding: His birth is the result of a technically "incest" between his father and his sister in order to attempt to obtain successor a more talented in magic. Because of this, his biological mother is also his aunt, and her legitimate daughter and his cousin, is his half-sister.
- Star-Crossed Lovers: He reciprocates Minami's feelings, but 1) she is a slave, 2) she belongs to a rival clan, 3) she has a really short lifespan, and 4) Minoru sided with the guy who's trying to kill her mistress.
- More Than Mind Control: On some level he really does think he's helping Minami by offering to put her under the Parasites' influence (because it would heal her injuries) and forcibly abducting her away from her masters (because she has been psychologically conditioned to accept her slavery). But if he were in his right mind he would care that he's violating her free will by doing so.
- Pretty Boy: He is so amazingly beautiful that Tatsuya immediately suspects he is a genetically improved magician. Moreover, according to others, only Miyuki can compare with him in beauty. Later in the 16th volume, this phenomenon is referred to as proof that Miyuki is also the result of genetic intervention.
- Voiced by: Hidenobu Kiuchi
- Cool Sword: Ikazuchimaru.
- Heir to the Dojo: He is the heir of the Chiba family
- Hero with Bad Publicity: Many see him as a slacker while he follows a rigorous training regimen.
- Voiced by: Susumu Chiba
- Affectionate Nickname: Mari calls him Shu.
- Bodyguarding a Badass: Was on security detail to watch Tatsuya during the events of Volume 9~11.
- Doppelgänger Spin: By cycling between charging and freezing he is able to produce afterimages
- Fandom Rivalry: In-Universe with Gonghu's fans.
- The Knights Who Say "Squee!": Is a huge fan of Kazama.
- Master Swordsman: He is the world's strongest swordsman.
See First High School
- Voiced by:
- Voiced by: Koji Yusa
- Big Bad: The main antagonist of the series.
- Named After Somebody Famous: Has the same name as Zhou Yu Gong Jin, an admiral of the Wu country in Romance of the Three Kingdoms. Known as Shuu Yu in Japan.
- Revenge: He wants to destroy the Yotsuba clan because they destroyed his country.
- Stealth Expert: Knows the Ghost Walker magic.
- Voiced by: Takahiro Fujiwara
- Animal Motifs: Tiger.
Angelina Kudou Shields
- Bodyguarding a Badass: In the recent volumes, after taking refuge to the Yotsuba Family due to parasites infiltrating the STARS, she becomes Miyuki's bodyguard as part of her disguise after Minami left with Minoru.
- Chekhov's Gunman: Shinkurou talked about a certain Major Sirius and his Molecular Divider during the Yokohama Disturbance arc.
- Dumb Blonde: Was created to be one though she is much smarter than the usual ones.
- Fantastic Nuke: Heavy Metal Burst.
- The Mole: Transferred at First High to inquire about the Shiba siblings.
- Overranked Soldier: She is the high Commander of Stars but is too young for this rank.
- Person of Mass Destruction : One of the thirteen revealed strategic-class magicians
- Red Baron: Angie Sirius.
- The Reveal: She is Angie Sirius, the strongest member of STARS, an elite force of magician soldiers of the USNA army.
- The Rival: Miyuki's official rival.
- Tsundere: She has feelings for Tatsuya that she loathes to admit.
- Skilled, but Naïve: As a soldier, her naivety is one of her biggest weakness.
- World's Most Beautiful Woman: She is considered as beautiful as Miyuki.
Silvia Mercury First
- Blow You Away: Can carry messages by using air vibrations.
- Brutal Honesty: To her superior Lina.
- Code Name: Silvia is her first name, Mercury First are code names.
- But Not Too Foreign: She has Japanese origins.
- The Mole: Infiltrated magic universities undercover.
- Shock and Awe: Electric balls.
- Double Reverse Quadruple Agent: Symbiotic Possession: She was actually being controlled by a Parasite
- Taking You with Me: Used a suicide attack when cornered to kill her opponents and possess a more powerful host. Defeated by Tatsuya, she ends up possessing Pixie.
- An Offer You Can't Refuse: After failing in her mission to uncover and neutralize Japan's secret Strategic Magician, Tatsuya, she ended cornered by the Yotsuba and accepted an under-the-table deal to stop her investigation in exchange for their assistance in dealing with the USNA defectors (actually possessed by Parasites).
- Older Than She Looks: She is in her forties but looks younger.
- Voiced by: Ryotaro Okiayu
- Bring It: To Tatsuya before beating him during their fight in episode 01.
- The Dumbledore/Manchild: Despite his reputation, he is quite childish and likes to play pranks on Tatsuya and tease Miyuki.
- Master of Illusion: Ninjutsu users are good at making illusions.
- The Mentor: To both Tatsuya and Miyuki, more on Tatsuya though.
- Ninja: Obviously.
Ushio KitayamaShizuku's father. he's a rich businessman.
- Amazingly Embarrassing Parents: Mostly due to being a Doting Parent.
- Doting Parent: Likes to spend time with his daughter.
- Happily Married: With Benio. And it was particularly difficult because he is not a magician.
- Nice Hat: A Greek hat.
Benio KitayamaShizuku's mother.
- Brutal Honesty: Her defining character trait.
- Happily Married: With Ushio.
- Marry for Love: As a talented magician she should have normally married another magician but overcame opposition to marry Ushio.
Wataru KitayamaShizuku's little brother. He is not a magician.
- Children Are Innocent: It is even lampshaded. Quite different from 10MC children.
- Humble Goal: Wants to become a magic engineer to help his sister.
Maki SawamuraA famous actress.
- Master Actor: Well, she is an actress.
- Mrs. Robinson: Rather ambiguous until she set up Takuma to sexually assault her. But Tatsuya ruined her plans.
- Slipping a Mickey: Gave alcohol to Takuma to set him up for Date Rape.
- Your Cheating Heart: Played with. She is supposedly engaged to one of Shizuku's cousin (no ring was given) but her relationship with Takuma is ambiguous to say the least.
Kokoa WatatsumiMore accurately, "Kokoa of the Watatsumi series". She is an illegally cloned magician whose escape from her creators initiated the plot of the movie The Girl Who Calls The Stars.
- Security Cling: She accepts the hug offered by Erika, and often hides her face in Erika's shirt when scared.
- Hidden Eyes: During Kokoa's enslavement, a fringe of shaggy dark hair covered her eyes. Since sight was irrelevant to her purpose, no one bothered to cut it.
- Powered by a Forsaken Child: Kokoa was the child, a fact the heroes find especially shocking because the Japanese Navy is only allowed to clone adults. She and eight other Watatsumi acted as a weapon's living battery, which eroded both their magic and their personalities.
- Replacement Goldfish: The main reason Tatsuya decides to help her is that her situation reminds him of Honami's.
- Undying Loyalty: Her first priority after finding shelter is persuading people to save her eight "sisters".
- Younger Than They Look: Due to malnourishment.