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"Siblings" (姉妹 Shimai?) is the sixteenth episode of the second season of the Toaru Kagaku no Railgun anime adaption, and the 40th episode overall. It was first aired on July 26, 2013. The screenplay was written Yamada Yatsumoto, storyboarded by Ohashi Yoshimitsu, and directed by Kasai Ken'ichi. The episode was co-directed by Komatsubara Sei, Naoya Takashi, and Kumagai Katsuhiro.

The secret plan that was made to empower Accelerator has beesunk to the ground by the right fist of Kamijou Touma.

Accelerator, the person which the secret experiment was built upon, is felled by the right first of Touma. Air, wind, atmosphere, all this was grasped by the hands of the Accelerator, all this through its vectors, to strike down Touma. All of this, is an attempt by the Accelerator to surpass being the "Strongest" and reach "Invincibility" at last, and in this, knocks Touma down.

As her surroundings tremble at the sight of Accelerator trying to achieve absolute power, Mikoto attempts to stop it herself, for she was the one who gave birth to this "experiment," and allowed this broken man before her to involve himself.――However, this would ruin Touma's plans in taking down the predictions of Tree Diagram by having the "Weakest" defeat the "Strongest."――

The only one who can stop this now are the "Sisters". With this, Mikoto asks for her sister, Misaka Imouto, to "protect his dream." Finally, it is come to the end Kamijou Touma and the Accelerator face each other once more for one final clash.


An overzealous Accelerator gloats at his newest achievement, the gathering of large quantities of plasma from manipulated air particles, now sitting atop the skies of Academy City. However, his moment of glory becomes short-lived as the plasma gradually dissipates into the air above him. Accelerator quickly notices the presence of "unusual" winds and assumes that wind manipulators are nearby. In fact, the cause of this disruption is the manipulation of the many wind turbines scattered across Academy City, possible by reversing the polarity of a turbine.

Accelerator then turns to the only person he thinks can produce this outcome — none other than the Sisters, who are in a united effort to disrupt his calculations. Enraged by this move of insurgency, Accelerator decides to finish off the only Sister in the vicinity, Misaka 10032. However, Mikoto prepares to defend her "younger sister" at all costs.

Mikoto stands firm in front of Accelerator, who questions her and Touma's conviction to save the Sisters despite considering them to be knockoffs of the original. In fact, Accelerator even points out that Mikoto has a reason to hate them more than anyone else. Misaka 10032 looks away with embarrassment as Accelerator continues to speak ill of her and Mikoto, especially the latter for making the experiments possible in the first place. However, Mikoto remains calm and rejects Accelerator's offer of becoming a god and, for the first time, calls her clones "sisters", much to Misaka 10032's surprise.

There, Mikoto declares that no one will die as long as she stands.

Accelerator simply laughs at Mikoto's dedication, calling her reason "retarded". Then, his smiling face turns into a scowl as he shows his increasing annoyance at the fact that he had to share the position of Level 5 with someone like Mikoto.

The strongest Level 5 prepares to eliminate Mikoto and her "sister", until the presence of another person on the battlefield re-emerges. Mikoto gasps in shock as Kamijou Touma, despite his grievous injuries, stands up.

Shock sets in as Accelerator fails to comprehend how Touma could survive something 10,000 clones could not. Meanwhile, Mikoto stops Misaka 10032 from coming closer to Touma. Although a bit shaken by this spectacle, Accelerator builds confidence that he can kill Touma with a single touch of his ability. In a split second, Accelerator leaps into the air and prepares to destroy Touma. The sudden attack startles Mikoto that her hand fumbles upon attempting to intercept Accelerator using her Railgun.

Accelerator swings his right hand and misses.

Accelerator swings his left and has his left index finger broken by the impact of Touma's right fist.

At that moment, all he asked was, "Why?"

Those memories of having a power so powerful that it can unite the entire world just to contest it... being confronted by scientists into participating in their projects... and the wish to gain absolute power that cannot be contested by anyone. All of those entered Accelerator's mind at that instant. Amidst all this, for the first time, Accelerator wonders what he has been doing all this time.

Then, Touma's fist connects with Accelerator's face, knocking him out on the spot.

With that, everything turns into a standstill.

Kamijou Touma wakes up later that night in a hospital room, visited momentarily by Misaka 10032. The next day, the Original shows up, although Touma was asleep when she arrived. For a moment, Mikoto remarks about how crazy Touma was in leaping straight into that fight, but soon decides to take a closer look at Touma's sleeping face. Unfortunately, Touma wakes up just as she slowly inches closer to Touma.

A bit startled by Touma waking up, Mikoto decides to go straight to the point and hands over the expensive cookies she bought before heading to visit him. Touma, however, prefers handmade cookies instead, expecting anyone would do the same thing. Mikoto flies into a rage, causing sparks to fly around Touma's hospital room.

After that rather frightening development, Touma mentions to Mikoto that one of her "sisters" had visited him the night before, and relays the news about the cancellation of the Level 6 Shift Project. Although Mikoto has caught wind of this news, she still puts herself to blame for everything that had happened. Touma points out that it was Mikoto who was responsible for the existence of her clones, but he considers it a good thing, as their existence allowed them to experience things a human being feels. For that reason, Touma tells Mikoto that her sisters wouldn't like it if they see her down because of it.

After the visit to Touma's hospital room, Mikoto heads to the courtyard where she stumbles upon Misaka 10032, who is reunited with her cat and is bandaged due to her injuries. Fortunately, Misaka 10032's wounds were not as serious as that of Touma's, as 10032 claims herself. At that moment, Mikoto thought that the reason why her clones thought of themselves as guinea pigs is because they were called as such by the people around her. However, she thinks that people can eventually change how these clones think of themselves if they start treating them like human beings too.

Mikoto seems interested in taking this first step. However, seeing 10032 get lost over the most trivial things like playing on a swing set on a nearby playground would make things difficult for her. To make things worse for Mikoto, she was mistaken for 10032's younger sister just because she owns Gekota merchandise. 10032 seems interested in making fun of Mikoto in front of the two children they saw in the playground, but she actually means good things for Mikoto, who just risked her life to saving her younger sister.

As the children continue playing on the swing, Mikoto and 10032 spend some time in the shade. Misaka 10032 feels that this moment seemed surreal, knowing that she should have been dead during the experiment held the night before. Then, she recalls on their reason for existence: to be killed in experiments alongside 10,031 of her fallen "sisters" — a reason now lost due to the efforts of the Original herself, Misaka Mikoto, and Kamijou Touma. Right now, they face the problems any person faces, particularly the need of a reason to exist.

Misaka 10032 pleads to Mikoto to stay by her side and help her find the reason to exist, admitting her request was selfish of her.

Mikoto quickly agrees.

Later that day, Uiharu and Saten are surprised to receive a request from Mikoto herself regarding the need of an available kitchen to bake cookies. In Saten's apartment unit, they began cleaning up the ingredients used, while talking about how relieved they are in seeing Mikoto return back to her normal self again. Mikoto, on the other hand, already has the cookies she prepared in a paper bag, although she seems reluctant to give it to him personally out of embarrassment.

As scenarios of what would happen if she gives the cookies to him whirl around in her head, Mikoto is accompanied by Touma, who is still in bandages and a crutch but seemingly recovered well. Mikoto is clearly shocked at the sight of Touma being out of the hospital earlier than expected, and Touma explains that he wanted to avoid the slowly rising hospital bills, as well as the wrath of a certain roommate in white. Touma then returns to question to Mikoto and proceeds to tease her again, but Mikoto ends up too embarrassed to even say anything in front of him.

Unfortunately for Mikoto, Touma already plans to head back home. Touma greets her goodbye using his nickname for her "Biribiri", and Mikoto finally manages to speak, pointing out that her name if Misaka Mikoto, not Biribiri.

Then, as Touma calls her "Misaka", Mikoto felt like her heart skipped a beat.

Moments later, Kuroko heads to where Mikoto is and she quickly panicked at the sight of Mikoto's face. However, Mikoto quickly manages to calm her down. It turns out that Kuroko is there to warn Mikoto that the Dormitory Supervisor has caught wind of their violations as of late. Mikoto seems calm about everything as opposed to Kuroko, and despite Mikoto's positive mood, Kuroko can't help but be perplexed...

...especially upon seeing a face that she hasn't seen in Mikoto ever.

Elsewhere, in a twist of luck, a Misaka clone finds a Gekota patch in a gachapon machine.

Major Events

  • With the aid of Mikoto and the clones, Touma is able to defeat Accelerator.
  • The Level 6 Shift experiment is suspended, and the clones are sent to facilities for readjustment on their bodies.
  • Touma refers to Mikoto by her family name for the first time.

Adapted from


New Characters

No new characters were introduced during this episode.


New Locations

No notable locations were introduced during this episode.


New Abilities

No new abilities were shown during this episode.


  • With at least 15 episodes dedicated to the story, the Toaru Kagaku no Railgun S version of the Sisters Arc is the longest story arc along with the Daihasei Festival Arc in the animated series.
  • Index makes a cameo appearance for the first time in Toaru Kagaku no Railgun S.


  • Episode 4 is referenced a few times during this episode. First, showing the cookie mold that the girls bought in Seventh Mist being used for the cookies that Mikoto should've given to Touma, as well as the gatchapon machine after the end credits, showing a Misaka sister acquiring a Gekota badge on her first try.

Cultural References

No notable references to culture are shown this episode.

Differences in Adaptation

Animation Trivia

  • 1 minute and 30 seconds of content are reused from the previous one as the recap sequence for this episode.
  • Scenes from episode 4 are used as a flashback for this episode.


# Title Time Scene & Notes
Unverified Track Opening
Unverified Track
Unverified Track Eyecatch
Unverified Track
Unverified Track Ending
Unverified Track Preview

Unanswered Questions

  • What happened to the unconscious Accelerator after the experiment?
  • What are the Sisters going to do now?


  • Mikoto: "I couldn't care less about being a god. And I don't think I can make up for my sins by doing this either. She's my sister. They're all my sisters."—to Accelerator.
  • Touma: "Grit your teeth well, 'strongest'. My 'weakest' attack... might shake you up a little!"—to Accelerator.
  • Accelerator: "Why...Why won't he break? Protect those puppets? I'm just one step away from absolute power! Why am I... One day, this power's gonna bring the whole world against me. It might destroy everything... If power breeds conflict, then I just need to have absolute power that no one'll ever contest. If I do that... one day, I'll... If I do that, I'll... I'll never have to...Seriously... What am I doing?"—internal monologue, just before being defeated.
  • Touma: "If you hadn't given them access to your DNA map, the Sisters would never have been born. There was a lot wrong with those experiments, but the fact that the Sisters were born is something to be proud of. If they hadn't been born, then they'd never have known happiness or pain. And I'm sure that they don't want to see you so down over it."—said to Mikoto.
  • Mikoto: "Lives created by machine. When they were born, they were blank slates. So if someone tells them they're guinea pigs, they'll think of themselves as nothing more than that. But if people treated them as human beings—like he did— then some day..."—internal monologue.
  • Misaka 10032: ""This is how you swing while standing up," says Misaka as she states the knowledge she gained through the Testament, as she becomes one with the wind."
  • Misaka 10032: ""That's no good. Big sisters have a duty to do whatever their little sisters ask," says MISAKA as she attempts to brainwash the girl while still young."—to little girl with a younger sister.
  • Misaka 10032: ""Pfft," says Misaka as she pretends to laugh. "She does have childish tastes for someone her age. She's also crude, short tempered, and quick to pick fights. On top of that, she's the type who won't admit to liking things.But she's my big sister, \Nwho'd even give her life for me.""—to little girl with the elder sister.
  • Misaka 10032: ""It's strange. Misaka was meant to die during last night's experiment. This was an expected outcome that had already been repeated 10,000 times. But even so... At this very moment, I am still alive. All Misaka were created for the purpose of being killed. That was our sole reason for existence. The reason we were created. But because of you and that boy, we have lost that reason. Downsizing. Unemployment. Roaming the streets without purpose. So... please stay with me, and help me find a reason to exist," requests Misaka, mustering all her selfishness."—said to Mikoto.
  • Mikoto: "It's not "Biribiri," it's Misaka Mikoto. Sheesh...The least you could do is remember my name. Though you might not have the brainpower to do it."—said to Touma.
  • Touma: "See you around, Misaka."


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