Characters: A Certain Magical Index Dark Side
The dark side of Academy City is the collective term for the seedier elements of the city that cannot be officially endorsed but are still part of backstage manipulations on the part of higher ups. Members of the dark side are uniformly amoral and at best manage to be antiheroes. The fifteenth novel revolves around the actions of five groups: GROUP, SCHOOL, ITEM, BLOCK and MEMBER, but there are also characters of ambiguous allegiance.Click here to go back to the main character page
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Voiced by: Anri Katsu
(Japanese) and Newton Pittman (English)
A friend and classmate of Touma, as well as his next-door neighbor at their dormitory. He's also a skilled sorcerer; however, undergoing the Power Development Curriculum causes his magic use to become fatal. His ability, Level 0 Auto-Regeneration, counteracts this, though imperfectly. He is a freelance spy for several organizations, including Necessarius, Academy City, and GROUP. The leaders are aware of this and lets him be for the time being.
- Anime Hair: As seen in the picture.
- Almighty Janitor: Like Touma, he's a labeled as a Level 0 for his ability. This doesn't diminish his effectiveness as a spy or a fighter in the least.
- Badass: Can easily defeat Touma in hand to hand combat, and the latter admits he would stand no chance against Tsuchimikado by himself.
- Brother-Sister Incest: Has feelings for his step-sister.
- Book Dumb: Like Touma, he's actually very smart outside the esper curriculum. And despite his reputation in school, he's also a highly-skilled onmyoji and an excellent spy.
- Bunny-Ears Lawyer: A shameless siscon with a Verbal Tic who happens to be a Reliable Traitor spy for Academy City, Necessarius, and a member of GROUP.
- Code Name: Fallere825
- Cool Shades: Is never seen without them.
- Embarrassing Nickname: "Siscon Sergeant". Yet he's proud of it.
- Fake Defector: Will very often pretend to betray his comrades, and often doesn't let them in on his plan.
- Fights Like a Normal: Because he can't rely much on his powers.
- His combat style is known as "Deadly Thrust Killing Slash", which incorporates a whole slew of martial arts styles and allows him to wipe the floor with just about anybody in close combat.
- Faking the Dead: As of New Testament 7, he is now believed to be dead apart from Seria, who helped to smuggle him out of the city.
- Foil: Like Touma, he consistently involves himself in both Magic and Science side affairs due to being a freelance spy. However, he generally has to tackle larger affairs compared to Touma's individual heroics.
- The Gadfly: Acts very annoying to everyone because it amuses him.
- Hawaiian-Shirted Tourist: Subverted. He's not a tourist, but is often seen wearing a Hawaiian shirt and sunglasses.
- Healing Factor: His Esper power, Level 0 Auto-Rebirth.
- Heroic RROD: The reason he doesn't use his powers if he can help it.
- Heroic BSOD: Goes into one in New Testament Volume 7 after hearing a false report that Maika had been murdered. It was so bad that he lashes out at Touma, who beats him unconscious with ridiculous ease and comments that there's no way it could have been that easy.
- Heroic RROD: Since he's a sorcerer-turned-esper, should he ever use magic it can kill him. Luckily his self-regeneration esper powers mitigates that. Sadly, he also mentions that his ability is imperfect (being a Level 0) and could fail anytime. He estimates he only has 5 or 6 "lifelines" left.
- Hidden Heart of Gold: He often says some really scary and unempathetic things while on the job, but is also repeatedly shown to be a good guy beyond that.
- Pragmatic Hero: As a member of the Dark Side of Academy City, he's not afraid to get his hands dirty.
- Not Blood Siblings: An excuse for why he has feelings for Maika.
- Onmyodo: He hails from a family descended from Abe no Seimei himself, and is a very talented onmyoji.
- Pretentious Latin Motto: "The Backstabbing Blade"
- Red Oni, Blue Oni: The blue to Pierce's red.
- Regular Caller: Since Volume 14, he's been dragging Touma for European missions, which comes to a head in Volume 17, where he uses knockout gas to bring him to London. Which makes this a rather literal case of "The Call Knows Where You Live".
- Reliable Traitor: He may backstab everybody, but you can always count on him when it is important.
- Self-Proclaimed Liar: He takes pride in it.
- Shipper on Deck: For Touma and Kaori Kanzaki.
- Tears of Blood: When he uses his powers, in addition to Blood from the Mouth.
- Those Two Guys: With Pierce.
- Verbal Tic: Nya!
- Weak, but Skilled: He's overshadowed by most of the mages and espers in the series in terms of sheer power, but he's an extremely deadly combatant nonetheless who can hold his own with them.
- Wild Card: Works as a freelance spy for either side, making him a Double Reverse Quadruple Agent. So far his straight loyalties only lie with his stepsister Maika.
She is the guide to the windowless building where Aleister Crowley resides and is a member of GROUP, forced to join when the city's Board of Directors captured her close friends and blackmailed her. Her ability is "Move Point", a ramped-up version of Kuroko's power in that she doesn't need to touch objects to teleport them. She is living with Tsukuyomi Komoe after losing to Accelerator in the Tree Diagram 'Remnant' incident.
- Achilles' Heel: Her teleportation is three seconds slower than Kuroko's, and she'll start coughing up blood from the strain if she teleports herself too many times in a row.
- Arc Villain: Tree Diagram Remnant Arc.
- Awesomeness by Analysis: Teleporters have to make calculations on factors like mass, volume, vector, etc. Normal scientists don't want to have to deal with it due to the 11th dimension coordinates involved.
- Bare Your Midriff: See Sarashi.
- Belligerent Sexual Tension: With Accelerator. They even mockingly call each other husband and wife.
- Coat Cape: Tends to wear her jacket like this.
- Combat Pragmatist: She just shoots Kuroko after the Villainous Breakdown.
- Evil Counterpart: To Kuroko.
- Girlish Pigtails: As seen in the picture.
- Heel-Face Turn: Mellows out after being "adopted" by Komoe-sensei.
- Magic Feather: Although not strictly necessary, she shines a flashlight on the spot she wants to teleport to to help her concentrate.
- Ms. Fanservice: Her outfit shows off a lot of skin.
- Sarashi: Wears this more often than a normal shirt.
- Shotacon: If the other members of GROUP are to be believed.
- Pragmatic Hero: Post Heel-Face Turn, she's a member of the dark organization GROUP, which is a group largely dedicated to keeping the peace through rather questionable methods.
- The Smurfette Principle: She's the only female member of GROUP.
- Superpower Lottery: The strongest Level 4 Esper shown so far, according to Word of God. She can teleport objects without even touching them and has more than twice the range and more than twenty times the haul load Kuroko does. She would have reached Level 5 had she not had... an unfortunate accident.
- Teleportation Sickness: See Achilles' Heel.
- Teleporters and Transporters: Her ability, Move Point, is basically Kuroko's power ramped Up to Eleven.
- Teleporter Accident: Teleported herself partially into a wall when she was younger and tried to pull herself out. The results were messy.
- Villainous Breakdown: When Kuroko points out her hypocrisy and how she's the problem, not her powers. The point is compounded even further when Kuroko tries to hurt her without her abilities.
Etzali (fake Mitsuki Unabara)
AKA the fake Mitsuki Unabara
An Aztec magician who was originally a member of Return of the Winged One. He was sent into Academy City to destabilize the growing Kamijou Faction, by sowing distrust into it's members. He is later defeated by Touma Kamijou himself, and later joins GROUP. He is usually referred to as "Unabara Mitsuki" as he has not told anyone in Academy City his real name.
- Badass in a Nice Suit
- Becoming the Mask: He was assigned to seduce (which he failed to do) and kill Mikoto, but fell in love with her.
- Berserk Button: Seeing Tecpatl use Tochtli as live ammo.
- The Dandy
- Deliberate Injury Gambit: Swords used for sawing bones aren't much good for cutting through them directly!
- Heel-Face Turn: Well, if you can consider GROUP to be good guys, anyway.
- Face Stealer: His primary power. While he only needs to steal a bit of skin to effectively take on a person's appearance, killing them to prevent them from running around at the same time has its advantages.
- Knife Nut: Wields an obsidian blade that is a replica of the Spear of Tlahuizcalpantecuhtli.
- Master of Disguise
- Meaningful Name: Derived from "eztli", meaning "blood".
- Murder the Hypotenuse: Attacked Touma, seeing him as a rival for Mikoto's affections.
- Not Himself: Not him personally, but when an assassin from his old organization comes after him he's shocked at how differently she's acting.
- Reliable Traitor
- Sharp-Dressed Man
- Stalker with a Crush: To Mikoto.
- Stalking Is Love
- Tome of Eldritch Lore: First he took Xochitl's to save her from dissolving, and later he outsmarted an opponent using the basic trait that the grimoires want to have their knowledge spread. So then he contracted with a second grimoire to help the first girl's friend.
- Unscrupulous Hero: After joining GROUP. Casually kills someone in a group being sent to attack him in order to copy his appearance (as in, ripped off part of his skin and put it on) and then when a telepath is checking to see if anyone is a spy uses plastic explosives to make someone else look like a spy and injure the telepath so that she couldn't check him. In his defense, he did feel bad about the second one and the first was trying to kill him.
- Wild Card: Let's remember that he won a proposed wager by Tecpatl for control over the Aztec organization. He hasn't done anything about it yet, but...
The fourth Level 5 esper, and the leader of ITEM. Her power, Meltdowner, converts electrons into a highly destructive form of matter that exists somewhere between particles and waves. While kind and gentle
to her friends, she has a unpleasant personality
- Action Girl: While reliant on her powers most of the time, she is quite tough and versed in hand-to-hand combat.
- Artificial Limbs: Replaces her missing arm and eye with masses of pure energy and later, literal Artificial Limbs.
- Ax-Crazy: When she's pissed off:
"Gya ha ha!! Oh, now where to start burning her? Maybe I should roast that little face of hers. Or maybe I should press against her pink *** and burn it pitch black!! Hey, what do you think, Hamazura? You'd better come out, cause I'm gonna burn her into a black mummy! Or can you still get off to fucking a hole like that!?"
"I'll count to three. If you don't come out, I'll burn Takitsubo's *** as punishment. Of course, if you'd rather just abandon her, then you can just sit there masturbating to the stench of her virginity being burned away."
- Barrier Warrior: She can make shields of energy that are tough enough to withstand Mikoto's electric attacks.
- Beware the Nice Ones: While she's a Cool Big Sis to her teammates, offending her is a bad idea. Pissing her off reveals a very different side of her. It gets worse when she turns into a psychopath after losing half of her face.
- Big Damn Heroes: Saves Accelerator in NT Vol 6 when he almost falls victim to Kakine's Shape Shifter Guilt Trip.
- Blood Knight: Battle-hungry? Check. Unnerving temper? Check. Obsesses over Shiage after their fight? Huge check.
- Came Back Wrong: Became even more psycho and unstable than before, with a Yandere crush on her killer, Shiage Hamazura.
- Character Development: Was once The Social Darwinist who looked down on Level 0's, later accepts Shiage as the better fighter even though he doesn't have powers because he beat her. Becomes much calmer and friendlier in New Testament. Case in point, when Last Order teases her because she can see her panties, Mugino simply laughs and walks away, while the old Mugino would have probably killed her on the spot. She also starts learning how to cook in an effort to be more normal. When a naked Cendrillon appears in her apartment, she takes the whole thing in stride... well, until she loses her temper after Cendrillon teases her about her feelings for Shiage.
- Comedic Sociopathy:
- "I'm the girl who killed your sister. Nice to meet you." — said casually to Frenda's little sister.
- Mugino is pretty good at this, such as this little exchange when she was giving Shiage a countdown to come out before she roasted Rikou. Mugino did not give a nice slow count, as was usual. Instead…
: Three-two-one-go! Shiage
- Continuity Cameo: Along with the rest of ITEM, in Episode 12 of Railgun. In the manga version of that scene, there was a completely irrelevant conversation that had nothing to do with the plot.
- Cool Big Sis: To those she considers friends.
- Cute and Psycho: Her default personality.
- Cyborg: As of New Testament, she has one electronic eye and a cybernetic left arm. Her eye at least can be linked into security cameras with some wires.
- Defusing the Tyke Bomb: Shiage beats her twice, learning more about her state of mind in the process. She attacks a third time in what is intended to be a suicide attack by taking Body Crystal, causing her power to cause a sphere of destruction around her temporarily. After this, Shiage considers shooting her but decides not to, opting instead to at least try calming her down. It works.
- Disproportionate Retribution: Her form of payback.
- When Mikoto knocks her out in their fight, she wakes up a few minutes later, pissed about the headache.
- In the Febri arc of the second season of '"Railgun'', she shows up unexpectedly to blow up STUDY's robots simply because they tried to mechanically replicate her abilities.
- Do Not Go Gentle: When she teams with Accelerator against Kakine in NT Vol. 6, she says that maybe Kakine is right that she and Accelerator cannot be redeemed and will still go to Hell no matter what they do. Even so, they shouldn't just give up and die, they might as well kick some ass before they go.
- Effortless Amazonian Lift: Despite being a skinny teenage girl, she can Neck Lift grown men and throw them across the room.
- Even Evil Has Standards: She is sickened and horrified when she sees Fraulein Kreutune apparently eating someone, and remarks that she would have had the same reaction even if she were her old, evil self.
- Evil Cannot Comprehend Good: In Volume 22, she says it doesn't make any sense when Shiage has defeated her for the third time but spares her life. Shiage says that even after everything she's done to him and Rikou, he still cares about her. She calls him an idiot, but agrees to come with him.
- Evil Counterpart: To Misaka Mikoto, look down at the Not So Different below.
- Evil Laugh: "Gya-ha-ha!!"
- Foil: She specializes in destruction while Kakine specializes in creation. Pointed out in NT Vol 6.
- Frickin' Laser Beams: Her entire method of attack revolves around these.
- Beam Spam: Carries special silicon cards to facilitate this effect.
- Convection Schmonvection: Averted. Her beams are incredibly hot, and being near them can fry you.
- Mundane Utility: She can make a ball of energy to light her path.
- Power Incontinence: Her inability to control her own power is what led to her losing her left arm. If she had better control, she'd be the ranked as the third Level 5 instead of the fourth.
- Recoil Boost: She can cushion her fall or launch herself through the air by firing downwards.
- Required Secondary Powers: Subverted. She is not immune to her own powers.
- Sphere of Destruction: Surrounds herself with one in a last-ditch effort to finally defeat Shiage. He stalls until her energy runs out.
- Stuff Blowing Up: The end result of her power.
- Glowing Eyes of Doom: Her right eye, after she loses it in Volume 15 and before she gets an artificial one in New Testament.
- Hair-Trigger Temper: It doesn't take much to piss her off.
- Heel-Face Turn: Towards the end of volume 22, when she agrees to help reform ITEM.
- He Is Not My Boyfriend: Gets very embarrassed and loses her temper when Cendrillon teases her about her feelings for Shiage.
- Hoist By Her Own Petard: What ultimately defeats Shizuri in her first battle against Shiage is her own power blowing her left arm off.
- Implacable Woman. Seems to be the Level 5 most fond of this, especially during her first fight with Shiage. This backfires when Shiage proves she's Not So Invincible After All.
- It's Personal: In NT Vol 6, the reason why she decides to help Accelerator fight Kakine.
"And it isn't like I don't have my own reasons to be here. I was attacked by a false Frenda last night. You were the biggest factor of the darkness active at that time and the interest in playing with the dead was the same. I don't know what your purpose in that was, but I'm going to make you pay for disturbing her grave, you piece of shit."
- I Was Just Passing Through: In the final episode of Railgun S, she saves Mikoto from STUDY's robots. She had no idea Mikoto was there. She was just pissed at STUDY using her as a lab rat.
- Knight Templar: The kindest way of describing her.
- Lack of Empathy: Cheerfully greets the family of those she has murdered by introducing herself as the murderer.
- Laser-Guided Tykebomb: Over the course of numerous fights with Shiage, he comes to the realization that Mugino used to be a mostly normal girl who actually cared about her friends. Academy City just decided she's much more useful as their own personal assassin/enforcer.
- Locked Out of the Loop: Does not know about the magic side.
- Love Makes You Crazy: Inverted. In Volume 22, she's furious when she finds out that Shiage only remained a Level 0 because Academy City decided he wasn't worth their resources. This comes from a former Social Darwinist, by the way.
- Made of Iron: Her pain threshold is staggering. She can keep going after getting shot several times.
- Mama Bear: Has become one toward Fremea. In NT Vol. 6, she got really upset when Shiage lost track of her, meaning Fremea was potentially all alone in the city.
- Minor Injury Overreaction: Once went completely berserk after Mikoto gave her a small cut on her temple.
- Modesty Shorts: She only wears these occasionally.
- Ms. Fanservice: In NT2 she says that she's the level 5 in charge of sex appeal so she wears see through underwear.
- Morality Pet/Morality Chain: Since volume 22, Shiage seems to play this role for her. She's also become protective of Fremea.
- Murder the Hypotenuse: While trying to get revenge on Shiage, she tried to kill Rikou, because Mugino hates and loves Shiage at the same time. After her Heel-Face Turn, she seems to have accepted being #2 in Shiage's harem.
- Names to Run Away From Really Fast: She's a Level 5 esper with an ability dubbed "Meltdowner"...
- Not So Different: Both she and Mikoto have more in common than they realize: not only do their powers involve manipulation of electrons, but they also come from wealthy families, have an annoying yet lovable sidekick who adores them, are Cool Big Sises to their friends, are Genre Savvy enough to wear shorts under their skirts to avoid Fanservice, and tend to let their pride and anger win over reason. They would be best friends if they weren't enemies to begin with.
- Oh, Crap: In New Testament 5, when Frenda seemingly comes back to life and says she wants revenge for Mugino killing her back in Volume 15.
- The Only One Allowed to Defeat You: Towards Mikoto and later Shiage.
"Don't let pitiful bastards like that take your life. The one who's going to rip you to pieces is me!!"
- The Perfectionist: Here's Shiage's descriptions:
"The kind of person that can't stand it when you can't complete a video game without 100% accuracy."
"If you fuck up even slightly, you fly into a rage and won't accept it even if you complete the game."
"When someone like that fucks up even slightly, they find another goal in order to write it off. When you aren't able to get 100% accuracy, you instead go for a high score and are satisfied with that."
- Pride: Her biggest fault is her pride. It's because of this that Mikoto survived their battle, leading to ITEM's downfall and her death/defeat by Shiage.
- The Power of Love: In NT Vol 6, she declares that she's now running on her love for Shiage instead of her anger and pride, and that she's now stronger than ever.
- "The Reason You Suck" Speech: Gives it to Kakine while pointing out his Fatal Flaw.
- Sanity Has Advantages: If she wasn't so insane, she would have crushed Shiage easily without him being able to do the slightest thing about it. Or would never have ended up fighting him. Or wouldn't have even made an enemy of him in the first place. Sanity definitely has advantages.
- Shock and Awe: Has a very limited control over electricity, to the extent that she can make Mikoto's electric attacks turn away from her.
- Shut Up, Hannibal!/"World of Cardboard" Speech: Combines the two in New Testament Volume 6 when an enemy assumed that her love for Shiage and her guilt over killing Frenda would weaken her. Bonus points for her admitting without shame that she loves him.
"As long as I have Hamazura, this is fine. I'll get into trouble and into fights. There will even be deadly fights. But it will all work out in the end. No matter how many people I kill and how much I destroy, everything will be resolved in the end somehow and we can all be happy. All my past experiences have shown that to be true. That's how it was during the fight between ITEM and SCHOOL. That's how it was when we fought underground in District 23. That's how it was when we met during the fierce fighting of World War 3. And so I know it will be fine as long as I have Hamazura. No matter what happens, he will forgive me in the end."
- Sir Swears-a-Lot: Her mouth is NOT as beautiful as the rest of her face.
- Slasher Smile: Though she is quite fond of Kubrick Stares, Psychotic Smirks, and combinations of the three where applicable.
- The Social Darwinist: Played straight until Volume 22, where she subverts this by lashing out at Academy City's "Parameter List", a cost-control mechanism that restricts funds to unworthy (read: Level 0) students (read: Hamazura) and allocates those funds to more powerful and promising espers.
- Super Reflexes: She's fast enough to escape a bomb going off in her face, and to move away when somebody aims a gun at her.
- We Have Reserves: How she makes an enemy of Shiage, coupled with the fact that her "expendable" henchman had just tried a You Shall Not Pass for his sake.
- What the Hell, Hero?: Delivers one to Accelerator, saying that his Death Seeker attitude when it comes to atoning for his sins is just him taking the coward's way out. He takes it to heart, now determined to live to continue protecting his loved ones.
- Willfully Weak: It's strongly implied during the fight with Shiage that she's actually quite a bit more powerful than Mikoto, except she lacks immunity to her own power and as such has to limit herself. So she holds back on a large part of her raw power because if she truly went all-out with an attack, the recoil would kill her.
- Yandere: Towards Shiage, after he defeats her the first time. After her Heel-Face Turn, it turns into genuine affection, not that she would ever admit it to his face.
- You Have Got to Be Kidding Me!: When she learns about the Level 6 Shift project, she laughs and says it has to be one of the most ridiculous things she has ever heard.
- Zettai Ryouiki: In the Railgun S opening as well as the incoming episodes.
Second in command of ITEM. Her ability, Offense Armor, allows her to compress and solidify nitrogen in the atmosphere to act as a barrier, and is ranked at Level 4.
- Attack Reflector: She can use her nitrogen barriers as a limited version, since she graduated from the Dark May Project which studied Accelerator's powers.
- Barrier Warrior: Her ability, Offense Armor, is mostly defensive.
- Beware the Nice Ones/Let's Get Dangerous: DO NOT underestimate her. She's a Level 4 for a reason.
- Blow You Away: Nitrogen makes up 70% of the air, so she can generate small air currents by controlling the nitrogen.
- Buffy Speak: Talks like this almost all the time.
- Child Prodigy: The "honor student" of the Dark May Project.
- Cute Bruiser: It is Offense Armor after all. Her fighting style involves tanking hits, punching people, and throwing cars.
- Enfante Terrible/Tyke Bomb: She's twelve years old, and a remnant of the Dark May Project designed to replicate Accelerator's powers.
- Evil Counterpart: She has one in Umidori Kuroyoru, her kouhai from the Dark May Project, who first appears in New Testament 1. They have practically the same power, with Umidori's focusing on offense and Saiai's on defense.
- Immune to Bullets: Her Offense Armor lets her block bullets, which she does with no expression. Afterward, though, it becomes clear that it still really hurts.
- In the Hood: Wears an orange hoodie throughout the Sisters Arc.
- The Law of Diminishing Defensive Effort: Her Offense Armor is so durable that she's completely nonchalant about getting threatened by guns.
- Locked Out of the Loop: Does not know about the magic side.
- Meaningful Name: Her full name translates to "Beloved Silk Flag".
- Senpai: To Umidori Kuroyoru from their days in the Dark May project.
- She's Got Legs: She doesn't wear anything to cover her legs.
- Super Strength/Super Toughness: Subverted. To those unaware of her powers, it looks like her power is this, but all she's doing is controlling super-compressed nitrogen gas a few centimeters from her body.
- Sweater Girl: Wears these a lot.
- There's No "B" in Movie: Loves watching these kind of movies.
- The Tease: Loves to tease Shiage with her body, then call him a pervert.
- Verbal Tic: Super!
- You Shall Not Pass: Holds the line when Hisako Yukami attacks her and Shiage with man-eating cockroaches.
A member of ITEM. Her ability, ranked at Level 4, is AIM Stalker, which allows her to trace the AIM fields of other Espers.
One of the main combatants of ITEM, she has exceptional hand-to-hand capabilities.
- Adaptation Expansion: Receives almost no development in the Index storyline as Mugino killed her off fairly quickly after her debut in the novels, but Volume 5 of the Railgun manga rectifies this.
- Badass Normal: The only one of the four who hasn't shown actual esper abilities, she instead uses a combination of explosives and hand-to-hand combat to fight.
- Blood Knight: A mild example.
- Call Forward: In a horrific manner. When fighting against Mikoto after nearly getting her legs blown off, she notes that they are her best feature. Mugino kills her by severing her body at the waist.
- A popular Japanese meme is putting slashes or spaces in her name to memorate this.
- Came Back Wrong: In NT 5th volume. Subverted, when it turned out to be a man trying to defeat Mugino with a Shape Shifter Guilt Trip, which failed.
- Cute and Psycho: In battle.
"I said earlier that the target's life is of no interest, but I get a special feeling whenever I end them. That instant when you pluck a life, it feels like I've conquered their destiny. In the end...It's like they were born just to be killed by me."
- Dangerously Genre Savvy: Fills the room she and Mikoto are in with a mist that's not harmful to humans but will detonate if there's a spark, forcing Mikoto to fight without her powers. It ultimately was a bluff (see below), but it worked as she was a better hand to hand fighter than Mikoto.
- Dirty Coward: Was willing to sell out her team if her life was threatened. This would turn out to be her Fatal Flaw.
- Dropped A Bridge On Her: She is killed by Mugino off-screen for a betrayal that also occurred off-screen.
- Foreign Fanservice: One of the only non-Japanese characters from the Science Side.
- Girls Love Stuffed Animals: Her bombs take the form of stuffed animals.
- Half The Woman She Used To Be: How Mugino kills her.
- Hoist By Her Own Petard: Drops one of the devices she used to ignite the explosive strips after she filled the room with an "explosive mist", screwing over her entire bluff.
- Ineffectual Sympathetic Villain: Although she did rather well in her fight against Mikoto.
- Kick Chick: In the Railgun S animated adaptation at least, she seems to be a Tae-Kwondo practitioner who focuses almost exclusively on kicking in combat, including her preferred Coup De Grace with a bladed shoe.
- Mad Bomber: Minus the mad part. Mostly.
- Mundane Utility: She uses her explosives to open canned food.
- Rewarded as a Traitor Deserves: Is killed by Mugino for making a deal with SCHOOL, a rival organization, in exchange for her own life.
- She's Got Legs: At least she thinks so, and loves to flaunt them by exclusively using them in combat.
- Trap Master: Unfortunately, these traps lead to Mugino's downfall against Mikoto when she forgets to remove her traps.
- Verbal Tic: Basically!
- Zettai Ryouiki: Spotted sporting this in Railgun S' 17th episode.
Click here for his new look in NT Vol. 6
Academy City's second most powerful Level 5 esper, and the leader of SCHOOL. His ability, Dark Matter, allows him to create entirely new forms of matter that aren't bound by the laws of physics. Kakine's power is hinted to be related to Accelerator's in some way, and he is the only other esper with the potential to become a Level 6. He has a rather one-sided rivalry
with Accelerator, with his fondest wish being to defeat him.
- Affably Evil: Provided you don't directly oppose or hinder his objectives, he's actually a half-decent guy.
- And I Must Scream: His brain is preserved and forced to create a constant stream of Dark Matter after his "death" by Accelerator.
- Arrogant Kung-Fu Guy: He's incredibly confident in his own power, looks down on everyone else, and hates the fact that Accelerator is stronger than him.
- Asshole Victim/Laser-Guided Karma: He deserved everything Accelerator did to him.
- Awesomeness by Analysis: He can read past events in a given location by examining the impressions left in the surrounding area. He compares this to how a CD stores sound and images by having tracks etched in it. This was how he was able to imitate the Misaka Sisters for his Shape Shifter Guilt Trip.
- Badass: As the #2 Level 5, and considering how ridiculously powerful he is, Kakine definitely qualifies.
- Badass Boast: Delivers a lot.
Kakine: Are you making fun of me? Cause it sounds to me like you want to become a nice corpse.
Kakine: This is a difference in the freedom our powers give us. And that difference is insurmountable for you. I need not even do anything. I do not simply have an infinite supply of Dark Matter. My inspiration also knows no bounds. No matter how many cards you gather in your hand, I can push it back with brute force as numbers means nothing to me. Nothing you do will ever even reach me. To reach me, you first need to climb over the wall of infinity that continues on eternally.
Kakine: I don't care who you are. It doesn't matter what you've built up. I'm not interested in what you'll give to the world. Good and evil? Kindness and malice? Gain and loss? Positive and negative? We can let historians decide that a hundred years from now. All I know is what fate you deserve for trying to use me as a tool!!
- Berserk Button: When he's told his ability — more specifically, his white wings — would have appeal to kids for a demonstration during the Daihaseisai, he wrecks SCHOOL's hideout. Considering his one-sided rivalry with Accelerator, being told you have appeal to kids is the ego equivalent of a kick to the balls.
- Be the Ball: Othinus crushes him into a ball.
- Black Eyes of Crazy/Black Eyes of Evil: After his resurrection.
- Brain in a Jar: After his "dismemberment" by Accelerator, both his brain and body are preserved and stored separately. He eventually made a new body out of Dark Matter and was released. His original flesh and blood body was captured by GREMLIN at the end of NT Vol. 6. They use a device to force it to create Dark Matter that they can mold into the sacred spear Gungnir.
- Came Back Wrong: As of New Testament 5 he is officially back in the game, but all of his organs are now made with Dark Matter and Dark Matter is now a part of him.
- Curb-Stomp Battle: He spent Volume 15 one-shotting everyone he went up against without getting a scratch, until he went up against Accelerator.
- Death of Personality: Beetle 05 basically erased him and took his place. He later comes back in his old flesh and blood body, only to be stopped by Othinus.
- Evil Counterpart: He's Accelerator with less standards.
- Fatal Flaw: In NT Vol 6, Mugino points out that, despite his immense power, he always loses in the end because he overestimates himself and doesn't know how to quit while he is ahead.
- Foil: To Accelerator. Where Accelerator excels at destruction, Kakine's entire ability revolves around creation. This is actually lampshaded in NT Volume 5. In NT Volume 6, he is compared to Mugino the same way.
- Friend to All Children: After the protective side of him takes over (with Takitsubo's help) in New Testament 6 a rumor spreads which says that any child who is in trouble just needs to call for him and he will show up.
- Humanoid Abomination: After his resurrection.
- Heel-Face Turn: After Beetle 05 takes control of him.
- Hoist by His Own Petard:
- In Volume 15, Accelerator uses his own Dark Matter against him to finish him off, having learned how to redirect it even before Awakening.
- In NT Vol 6, he spreads his consciousness too thin, allowing one of the rhinoceros beetles he created to develop free will and then take him over.
- Imagination-Based Superpower: His ability, Dark Matter, allows him to create and control matter that does not exist in this universe and defies the laws of physics of everything it makes contact with.
- Jack Bauer Interrogation Technique: When Uiharu wouldn't tell him the location of Last Order, he tries to get the information out of her by stomping on her shoulder, dislocating it, and continuing to put pressure on it.
- Jerkass: Even worse than Accelerator.
- Lack of Empathy: Just as much as, if not more than, Accelerator.
- Light Is Not Good: Despite his angelic appearance and using weaponized light as his main attack, Kakine isn't a very nice person.
- Meaningful Name: His name can roughly be translated as "Emperor of the Front Fence".
- Not Worth Killing/Pragmatic Villainy: He has absolutely no compassion or remorse, but he will sometimes leave his opponents alive if they are completely helpless or already dying, just because he thinks it would be beneath him to waste energy on them.
- Pitiful Worms: Uses this line on Accelerator at one point.
Kakine: Be crushed by the symbol of your own sins and die, you worm.
- Phlebotinum-Handling Equipment/Tricked-Out Gloves: Wields the Pincet Glove aka Tweezers, which allow the wearer to pick up and manipulate microscopic things like nanobots. The Pincet Glove used to be a very bulky and impractical device, but Kakine modified it to comfortably fit on his hand.
- Protectorate: Beetle 05 has vowed to protect Fremea Seivelun.
- Punch Clock Villain: When he's not hired for something, he's somewhat normal.
- Redemption Demotion: After the Split Personality Takeover, he does not actively use Self-Duplication to prevent his previous personality from taking over.
- Satellite Character: His entire character is defined by his relationship with, and inferiority to, Accelerator.
- Shape Shifter Guilt Trip: In NT Vol 6, after Accelerator effortlessly destroys his army of copies, he then makes an army of copies that look, sound, and act like the Misaka Sisters. Accelerator falls into despair, unable to harm them, and is almost killed until Mugino steps in and reminds him that they aren't actually the Misaka Sisters, just extensions of Kakine. This restores Accelerator's will to fight.
- Split Personality Takeover: In NT Vol 6, one of the rhinoceros beetles he created, Beetle 05, develops free will. Not wanting to harm anyone, it gains the strength to take control over all of Kakine's creations. It disintegrates them, then transforms into Kakine and declares he is now him. Accelerator and Mugino muse that this beetle must have held the part of Kakine's personality that actually cared about others, buried deep down.
- Ungrateful Bastard: Stabs Yomikawa just after she saves his life from Accelerator.
- Unwitting Pawn: His hatred and envy of Accelerator was nurtured and encouraged by Crowley. He was also intended to act as a spare part in Crowley's plan, in case Accelerator failed to live up to his expectations.
- Villain Ball: Stabbing Yomikawa just to piss off Accelerator.
- The Worf Effect: As soon as the original Kakine comes back to life, Othinus crushes him.
- "World of Cardboard" Speech: Not him actually, but his creation Beetle 05. When Beetle 05 starts to develop free will, Kakine mocks him and starts to subsume him, saying he has no hope of becoming anything more than Kakine. Beetle 05 thinks it over, then says that's right, he has no hope of becoming anything more than Kakine. See Split Personality Takeover.
- Would Hit a Girl: Let's see: He fights with and defeats Mugino, attacks both Saiai and Rikou and leaves them for dead, nearly kills Uiharu, wanted to use the innocent and adorable Last Order as bait so he could have a glorified pissing match with Accelerator, and then stabs Yomikawa after she saves his ass from Accelerator.
- Zerg Rush: His strategy to fight Accelerator in New Testament Volume 6, sending his neverending army of copies against him.
The girl in a dress
An unnamed character and a member of SCHOOL. Her ability is "Measure Heart", the ability to regulate the distance between peoples' minds (hearts).
- Genre Savvy: Makes it out of the battle royale alive since she refused to follow Kakine to his fight with Accelerator.
- Also because she knows her power well and is already aware of how it can backfire.
- Gold Digger: Somewhat. She scams money out of lonely workers by comforting them, but she stops before anything more happens between them.
- Grenade Launcher: And it somehow fits in her purse.
- The Gunslinger: Wields a lady's handgun.
- Lady in Red: Often wears a sexy red dress.
- Nominal Importance: Averted. She's the most developed unnamed character in the novels.
- No Name Given
- Punch Clock Villain
- Sword Cane: That can slice through metal.
- What Kind of Lame Power Is Heart, Anyway?: Her ability regulates the distance between peoples' hearts...
- Heart Is an Awesome Power: ...which she can use to confuse enemies by making her distance identical to someone else's. For example, when Shiage points a gun at her, she makes her heart identical to Rikou's, causing Shiage to hesitate pulling the trigger. Objectively, Shiage knows Measure Heart is different from Rikou, but his heart is telling him he's targeting Rikou. On the other hand, she notes that some targets will go berserk and attack you harder because seeing a loved one as an enemy results in a betrayal response. This is why she does not go with Kakine to help against Accelerator: She reasonably enough thinks he might be that type. Her power is so dangerous that Mugino is wary of fighting her.
A replacement sniper hired by SCHOOL after their previous sniper was killed by ITEM. He is known to be a mentor figure to Stephanie Gorgeouspalace.
- Big Brother Mentor: To Stephanie Gorgeouspalace.
- Cold Sniper: In contrast to Stephanie Gorgeouspalace.
- Hired Guns
- Ironic Death / Tempting Fate: He's not dead, but he once said that he'll never be killed in an explosion no matter what. Cue Saiai bringing in an anti-tank warhead.
- Mentor: To Stephanie Gorgeouspalace.
- Mentor Occupational Hazard: Subverted. He survives the explosion, but he is grievously wounded and kept by Thomas Platinaburg as a bargaining chip to hire Stephanie.
The elderly, unnamed leader of MEMBER.
- Einstein Hair: As seen in the picture.
- Measuring the Marigolds: Whenever he looks at art, a landmark, or a natural wonder, he sees not its natural beauty, but its inherent mathematical formulas. He considers those to be beautiful.
- Nanomachines: He used these, called Mimosa, during the battle with SCHOOL in Volume 15. They can enter people and tear them apart from the inside out. Unfortunately for him, Kakine had the means to detect them and used his ability to fend them off before killing the Professor.
- No Name Given: He is only referred to as the Professor.
- Secret Keeper: The only member of MEMBER who knew that Xochitl was from the magic side.
- Smug Snake: He believed Mimosa was all he would need to kill Kakine. Boy, was he wrong.
A hacker who works for MEMBER. He supports the professor from a shelter known as "Summer Resort" with his remote controlled animal robots. He also appears in the Railgun Daihaseisai Arc when he tries to capture a SISTER clone.
- Awesomeness by Analysis: Analyzes and develops counters to an esper's abilities.
- Badass Normal: Has no known ability.
- Combat Pragmatist: Attacks people from a distance with his robots.
- The Cracker: Part of what he does as Mission Control.
- Freudian Excuse: He was bullied and people wouldn't trust him, so he doesn't trust anyone and likes to make people suffer.
- Jerkass: Looks down on and insults everybody.
- Left for Dead: The last time we saw him the underground shelter he was using in Volume 15 is flooded presumably by SCHOOL. This leaves him trapped with no method of escaping drowning.
- Mission Control: Often assumes this role.
- Smug Snake: Is a bit too overconfident.
- Robot Master: Uses robotic Great Danes to fight for him, and robotic mosquitoes for more covert actions. He also has an unwieldy robotic praying mantis if he really needs the extra firepower.
- Villainous Breakdown:
The Corpse Specialist
A sorcerer from the Aztec organization Return of the Winged One, punished by being ordered to infiltrate Academy City and kill Etzali (the fake Unabara Mitsuki), joining MEMBER in the process. The Professor seems to be aware that she is a sorcerer. She was also a Protagonist in Railgun SS.
- Barely-There Swimwear: In the Railgun SS. When she convinces Saten to get her a bikini to move around unnoticed in, Saten gives her something that Kuroko would wear...In fact, see for yourself◊. Her measurements are "84, 58, 81" for the record.
- Big Damn Heroes: Three times. She saved Saten from being killed by Olive Holiday and being crushed in the Railgun SS, and from Kouzaku Mitori in Railgun manga.
- Cool Airship: The Mixcoatl
- Cool Sword: "Macuahuitl", a sword that's used to saw through human bodies.
- Awesome but Impractical: Etzali makes use of the fact that a sword used to saw through human bodies isn't well suited for slashing through them directly.
- Hammerspace: One of her abilities.
- Master of Disguise: Like Etzali, she can use the skin of others to disguise herself.
- Meaningful Name: Nahuatl for "flower".
- Odd Friendship: With Saten.
- Rewarded as a Traitor Deserves: After going against her superior's orders by teaming up with Mikoto in the Railgun SS.
- Body Horror: A grimoire was forcefully pushed onto her body, turning a huge portion of her body to dust and was replacing it with artificial tissue.
- Senpai Kouhai: A junior to Etzali.
- Necromancer: Her original magic centered around speaking with the dead.
- Used to Be a Sweet Kid: Etzali described her as afraid of violence, however when the Grimoire was implanted...
- Wild Card: Given she is a Double Agent.
A girl who acts as a liaison between MEMBER and the Board of Directors. She first appears in the Railgun
version of the Daihaseisai Arc. Her ability allows her to control a duplicate of herself made out of liquid metal.
- Dark and Troubled Past: As a child, she was Dolly's best friend Mi-chan, who stopped visiting her after she was horrified by Dolly's life-support implants. She tried to have Dolly rescued from the facility by arranging a terrorist attack, but failed and was locked up in the Reformatory (juvenile hall). It was here that she was recruited into the Dark Side.
- Death Faked for You: This occurred when she was recruited from the Reformatory.
- Evil Cannot Comprehend Good: Remarks that she thinks people who live peaceful lives are "oddities".
- Genki Girl: She acts eternally cheerful because she has been in the Dark Side so long she has become desensitized to it.
- Girlish Pigtails: As seen in the picture.
- Only Friend: Dolly, the only person who could make her truly smile.
- Remote Body: Her ability allows her to make and control one from a kind of liquid metal. It reverts to a puddle if she gets too far away from it. She can hear but not see through the puppet, but compensates by having the puppet carry a video camera.
- Shapeshifter Weapon: Her liquid metal clone can form knives and other weapons from its mass.
- Stepford Smiler: As a child, she acted cheerful even though she could not stand the researchers because it made them trust and underestimate her.
- What Beautiful Eyes: Gensei Kihara said this about her, because her eyes were full of hatred.
- Whip It Good: Carries a riding crop.
A mercenary hired by Thomas Platinaburg in order to dispose of Accelerator. A friend of Sunazara Chimitsu.
- Badass Normal: Takes on Kinuhata Saiai without using any powers. Being a former Anti-Skill trainee, she knows how to suppress espers without using lethal force.
- Boxed Crook: She is eventually released from prison in exchange for helping Anti-Skill.
- Friendly Sniper: In contrast to Sunazara, who says that her tactics are an outrage to assassins.
- Gatling Good: She is skilled enough to incapacitate someone with a gatling gun without killing them.
- Genre Savvy: Shows up to her meeting with Thomas Platinaburg already well aware of his attempts to rig Sunazara's body with a device to blackmail her with. She quickly reveals that she has already removed said device and implants it into Thomas instead.
- Kick the Son of a Bitch: Kills Thomas Platinaburg after she finds out that he was tampering with Sunazara's body with machines in order to force Stephanie to cooperate.
- Revenge: Decides to avenge Sunazara by hunting down Saiai Kinuhata.
- Technical Pacifist: Her fighting style is designed so that she can apply only the necessary amount of force without being lethal.
- There Is No Kill Like Overkill: She originally thought it was best to use a missile launcher then a sniper rifle to assassinate. Proven otherwise because such overkill make harder to prove the death.
- Well-Intentioned Extremist: She only became a mercenary in order to protect the peace that she used to live in.
Umidori Kuroyoru is a sadistic girl and a remnant of the Dark May project who leads the mysterious Freshmen
- Abusive Parents: Played for laughs, Misaka Worst "adopted" her. And what does she do first? She constantly loves taking control of her like some puppet master, and makes her cry. Yeah...some mother of the year.
- Awesomeness by Analysis: Uses Kihara Amata's vector values and inputs them into her nitrogen lances, making Accelerator's vector shield useless.
- Ax-Crazy: Oh yeah, big time.
- Bare Your Midriff
- Break the Haughty: Misaka Worst torments her so hard she cries.
- Brick Joke: Touma invokes the possibility of her having cyborg cat ears underneath the raincoat she always wears. She denies this. Cue Misaka Worst barging in later on, saying she found "optional parts," specifically cat ears and cat paws gloves. Kuroyoru screeches when she hears this.
- Cat Girl: New Testament Volume 2 foreshadowed this heavily.
Umidori: There isn’t going to be some strange development where it turns out I always wear my hood in order to hide cat ears!!
Misaka Worst: Heeeyyyy!! Misaka attacked a few Freshmen strongholds and found some fun optional parts! Let’s have some fun remodeling that cool narcissistic girl with these cat ears and cat paw gloves!!
- The inevitable happened in New Testament Volume 3: Misaka Worst has "adopted" her and calls her Kuronyan.
- Card-Carrying Villain: At any chance she gets, she insists that she's a villain that loves the darkness and destruction that's out to destroy the Graduates (Accelerator, ITEM, Hamazura to name a few).
- Couldn't Find a Pen: After she gets curb-stomped by Rensa and is barely able to talk, she writes in her own blood to tell Shiage about Rensa.
- Cry Cute: In New Testament Volume 3 when Misaka Worst takes her teasing a little too far:
- Curious Qualms of Conscience: While under the effects of Agitate Halation, she finds herself unable to abandon Fremea.
- Cyborg: She uses this to augment her power. Since "Bomber Lance" is fired from palms, she attaches hundreds of mini-arms to her back. She can also detach pieces of her body like her arms. Apparently the yearly surgeries to maintain this ain't worth it, according to her.
- And it doesn't help that Misaka Worst is an electromaster that can completely dominate her because of this.
- Dark Action Girl: Just look at her. Nothing is left to be said.
- Dark and Troubled Past
- Emotionless Girl: When she's not being ax crazy or a jerkass, she seems to be this.
- Shiage can't seem to understand why she and Misaka Worst were so bored when their lives (as well as the people) were in danger.
- Enfant Terrible/Troubling Unchildlike Behaviour: Merely 12, and she's indulges in death and destruction. Most likely due to adapting to Accelerator's thought patterns.
- Evil Counterpart: To Saiai.
- Evil Feels Good: She gives Accelerator a small speech about it too.
- Even Evil Has Standards: Invoked. In her own words, after being locked up in Touma's bathroom:
: And even as a member of the darkness, confining a twelve-year-old kid in the bathroom and removing both her arms seems really fucking
twisted to me!!
- Expy: She's Azusa from K-On!, except she's a psychopath.
- Glass Cannon: Since her powers and strategy concentrate so much on offense, she has weak defense.
- Heroic RROD: See Yin-Yang Bomb below.
- Kouhai: She was the kouhai of Saiai Kinuhata during the Dark May project — her as the rebellious punk.
- Meaningful Name: "Kuroyoru" can be roughly translated as "Black Night", and "Umidori" can be translated as "dolphin". Roughly, her name means "Dolphin of the Dark Night".
- Mood Whiplash: Gets this hard when she goes on a hurtful tirade and tries to kill Touma, only to have him casually dismiss her and start talking about cyborg cat ears!
- Multi-Armed and Dangerous: Her power allows her to project lances of compressed nitrogen from her palms. Because she only has two palms, normally she can only produce two lances. The solution to the problem...modify herself with cyborg arms to give herself lots of palms. Problem solved.
- My God, What Have I Done?: When fighting Rensa, Umidori thinks that Shiage is preparing to betray her and thus doesn't follow through on his plan. This results in him nearly getting killed when she didn't follow through. This combined with the lack of blame causes her to have a bit of breakdown.
- Not So Different: Accelerator gets a little creeped out by the fact that she's a mirror image of his old self.
- Literally, as a product of the Dark May project, she has Accelerator's offensive cognitive patterns in her brain. Kuroyoru happily lets her psyche be affected by the old Accelerator's thought patterns — unlike Saiai, who more or less controls herself.
- Odd Action Duo: Her and Misaka Worst.
Misaka Worst: How about we join forces as the villain girl combo?
- Precision F-Strike: Her first meeting with Accelerator.
Umidori: There was something I wanted to ask you if I ever met you. I had actually completely forgotten about it, but I remembered it when I saw your face. So I guess I’ll ask you now.
Umidori: …Do you really fucking think everyone in the world can just get along?
- Suspiciously Specific Denial: She does not have cyborg cat ears! STOP ASKING!
- Taking You with Me: Tries to kill Fremea in a last ditch effort. Thankfully, a certain someone stops her. It's Touma.
- There Is No Kill Like Overkill: Her cyborg arms allow her to spam her ability.
- Villain Ball: She thinks just like the reckless, prideful, and A God Am I over-confident Accelerator from Volume 3. When she fights Accelerator, the simple fact that he sidesteps her attack — completely diverting from his original self who would've stood head-on, and thus what Kuroyoru thinks — ends up completely bewildering her, leading to her defeat.
- What Happened to the Mouse?: Everyone left her for dead in Touma's bathroom in New Testament Volume 2.
- She's brought along to Hawaii to fight GREMLIN.
- Yin-Yang Bomb: After listening to Leivinia Birdway's lesson about magic, she develops a technique where she channels AIM into her cyborg parts, then attempts to cast a simple spell. The AIM and mana react and trigger an explosion and mini-earthquake. Doing this damages her cyborg parts, but leaves the rest of her relatively intact.
Baggage City Assault
One of the three Kiharas sent to attack Baggage City.
- Badass Transplant: She has Equ.DarkMatter implants, made using Kakine Teitoku's ability, that allow her to use powers despite not being an esper.
- Evil Cripple: A wheelchair-bound woman who is just as immoral as a Kihara can get.
- Off with Her Head!: Kagan Kihara slashes her head with his sword, then rips it off with his bare hands.
- Meaningful Name: Her given name means "Pathology".
- Super Wheelchair: It is armed to the teeth with weapons, and can transform into a spider-like mecha.
- Wounded Gazelle Gambit: Often pretends to be a kind, helpless woman to make people drop their guard.
One of the three Kiharas sent to attack Baggage City. He uses various chemicals, developed from the Mental Out Five OVER project, to produce illusions.
- Honor Before Reason: Part of it is sadism, but he prefers to toy with an opponent with his illusions before killing them, because killing someone right away is too boring.
- Master of Illusion: His skill with creating illusions with chemicals is roughly equal with Útgarđa-Loki's skill with creating illusions with magic.
- Meaningful Name: His given name means "Random Number".
- Morton's Fork: Gives one to one of the Science Guardian leaders for his own amusement. The man's wife, daughter, son-in-law, and two grandsons were rigged with guns. The man had to pick one to be shot, and Ransuu claimed only one gun was loaded, when in reality they all were. The man picked his son-in-law, but fortunately, his entire family was rescued from under Ransuu's nose.
One of the three Kiharas sent to attack Baggage City. She is capable of mimicking other peoples' thought patterns.
- All Your Powers Combined/Power Copying: She doesn't actually gain their powers, and she can only use them one at a time, but by mimicking other people's thought patterns, she gains access to their skills. She has access to over 5,000 people's thought patterns.
- Awesomeness by Analysis: In her captivity, she learned advanced science by observing everything in her room.
- Book Dumb: She doesn't know basic math or how to write katatana because she has never been taught these things. She is still a super genius.
- Combat Pragmatist: Uses numerous gadgets and improvised weapons, including toxic mold.
- Fashionable Asymmetry: Her boots don't match. Also, her stockings are torn up randomly.
- In the Blood: When she was very young, some rivals of the Kihara family kidnapped her and kept her in isolation. Despite no basic education, she still became a scientific genius with no regard for the victims of scientific research. She eventually escaped and rejoined her family.
- Little Miss Badass/One-Man Army: This middle schooler had the highest body count during the Baggage City assault.
- Meaningful Name: Her given name means "Circumference".
- "Well Done, Kihara" Girl: She is always trying to prove herself as a Kihara.
A Kihara sent to negotiate with the leaders of the Science Guardians after the events in Baggage City.
A new Cyborg developed by Academy City to match up with the Level 5 Espers; serves Yakumi Hisako.
- Ax-Crazy: Number 29.
- All Your Powers Combined: Can replicate the 1st through 6th level 5 esper powers and also any other esper within 200 meters. She can only use one power at a time.
- Brain in a Jar: More specifically a hypothalamus in a jar, the one part of a human body that cannot yet be replicated by Academy City. After her body is destroyed, Touma salvages 40 of the brains and puts them in cold storage until something can be done about them.
- Confusion Fu: Her facial expression doesn't change, she barely has any body language, and her involuntary muscle movements like blinking and breathing are completely regular. This makes it very difficult to predict her in battle. Ultimately, she can't keep it up forever, especially if she gets upset.
- Dark and Troubled Past: Invoked by Number 29 to explain why she chose to become a cyborg. She assumes Number 28 had a similar experience.
- Dramatic Irony: In her speech to Touma, she seems to regard him as a complete greenhorn at heroism and unaware of the dark side, claiming that he never been in a situation where he couldn't save everyone before, and noting that he still has all his limbs and organs intact. This to a man who has saved the world several times, battled the dark side of Academy City and the magic factions, and lost his right arm four times.
- Emotionless Girl: Number 28.
- Expy: Artist notes indicate that Number 29's design is based on Envy from Fullmetal Alchemist.
- Feel No Pain: As a cyborg, she can shut off her pain receptors.
- Frame-Up: Part of her plan involves murdering Fremea and pinning the act on Umidori. Fortunately, she is foiled.
- Heroic Sacrifice: Dies in order to protect Hisako Yakumi.
- Hospital Hottie: Number 28 has a day job as a nurse.
- The Nicknamer: Number 28 tends to call people by descriptions instead of their names, like "Fatty", "Wrinkly", or "Mr. Psychedelic".
- Power Copying: Can copy the power of any esper in a 200 meter radius. However, she couldn't copy Gunha Sogiita's powers because his powers are not understood by anyone. She cannot use a power as well as the original, especially if it requires vast computational powers like the Level 5s' powers. If an esper dies, she cannot copy his or her power anymore. When she tries to copy Imagine Breaker, it blows up her arm.
- Transformation Is a Free Action: Averted, she as a .7 second delay between powers. Of course making use of it is hard.
- Undying Loyalty: To Yakumi.
- You Are Number Six: Rensa is actually a single body with multiple different brains that can uploaded into her. Each brain is referred to as a number.
A Level 3 with the ability Mental Stinger, which gives her mental powers similar to Misaki Shokuhou.
- Animal Motifs: Her last name means "honeypot ant". She describes herself as an ant that wants to be a bee (Misaki's Animal Motif), and her Five Over OS (Outsider) - Modelcase Mental Out device looks like a bloated honeypot ant.
- Bungled Suicide: After being passed over in favor of Misaki and failing to meet Touma, she tried to kill herself, but failed. She then devoted her life to getting revenge on Misaki.
- Combat Pragmatist: Since her powers are not as strong as Misaki's, she utilizes several devices to even the score. She even pretends to be affected by Misaki's powers, then attacks her when she drops her guard.
- Development Gag: Her character design was in fact based on a rejected concept art for Misaki. According to Word of God, such rejected designs would be locked away. But since Ayu's role would be of a girl who wanted to be Misaki (a Level 5 with mental powers and a connection to Touma) but failed to do, using an old design for Misaki was fitting.
- Evil Counterpart: In the past, she and Misaki were roughly equal in power and potential. However, the higher-ups of Academy City decided to devote more resources to Misaki's development and essentially kicked her to the curb. Filled with despair, she learned of Touma Kamijou and tried to send him a message, asking him to help her, but then he met Misaki for the first time and didn't notice her message as a result. This filled her with burning hatred for the unfairness of the world. She is basically a Misaki who did not receive the same privileges and best friend.
- I Just Want to Be You: Her ultimate plan was to drain Misaki's memories into herself, leaving her a vegetable, so that she could have her happy life and past friendship with Touma. When Misaki manages to resist, she aborts the plan and just tries to kill her.
- Ironic Name: Ayu means "love" and "joy", which does not describe her at all.
- Magic Feather: Similar to how Misaki focuses her powers using remotes, she focuses her powers by pointing cameras or her fingers at her target.
- Mind Manipulation: Mental Stinger works by manipulating moisture, controlling the distribution of fluids and the secretion of chemicals in the target's brain.
- The Resenter: Hates Misaki for becoming the #5 Level 5 instead of her and for being saved by Touma instead of her.
- Villainous Breakdown: When she is about to kill Misaki and gloats that there is no hope for her, Touma arrives to save the day. Ayu goes crazy, complaining that it is not fair that he'd save Misaki even though he never received any message from her and it is practically impossible for him to learn about her murder attempt while he didn't save Ayu back then due to a similar lack of information.
- Walking Wasteland: During bouts of extreme emotion, she can cause the area around her to suffer a freeze-drying effect. Living beings within are drained of water and crumble apart.