Toaru Majutsu no Index Wiki
Toaru Majutsu no Index Wiki

"When You Work Under the Sun, You Need to Stay Hydrated" (炎天下の作業には水分補給が必須ですのよ Entenka no Sagyō ni wa Suibun Hokyū ga Hissu desu no yo?) is the second episode of the Toaru Kagaku no Railgun anime series. It was first broadcast on October 9, 2009.

Uiharu and Saten were invited to Mikoto's room at the Tokiwadai Middle School Girls' Dormitory. Mikoto and the others become excited about doing the typical things done in that situation like rummaging for swimsuits and looking at photo albums. But Kuroko, who wanted to celebrate her first month as roommates with Mikoto (as she pleases) is less enthusiastic about it. After Kuroko meekly told her earnest thoughts to Mikoto, Uiharu and Saten are saddened by it, while Mikoto ends up kicking her as usual. Kuroko's excessive actions were punished through an intense electric shock, and a fierce battle between esper abilities unfolded. They are then reprimanded by the dorm supervisor upon hearing the ensuing commotion, and the two are assigned to clean the pools...


In the morning of a fine summer, Misaka Mikoto is running in the footwalks of that advanced city, as if in a hurry. She stops at a pedestrian lane, waiting for the signal to change. She is panting heavily, an obvious sign that she has been running quite tremendously. However, she starts looking around, as if looking for something, and at the back of her, a spiky-haired young man tip-toes his way out of her sight. But she notices as the young man bolts it, and Mikoto gives chase across the pedestrian lane. Running, the man takes a turn into an alleyway, with Mikoto close behind. As if some dark machinations of misfortune, the young man comes across a dead end, and immediately after, Misaka Mikoto, the strongest Electromaster in Academy City, the third in the rankings of the Level 5's confront him. She smiles arrogantly, finally catching her prey. The young man begs for her to wait, but Mikoto does not listen to him. Suddenly, Mikoto uses her electric powers to attack the seemingly defenseless young man, as if uncaring for the laws that are the foundation of a functioning society. However, the man holds out his right hand, as if in defense, and a strange sound rings out. Mikoto's eyes are wide opened and the place falls into silence. Outside, Mikoto looks up to the blue sky, apparently in a stupor after what had happened. Then she hears the calling of Uiharu Kazari and Saten Ruiko, concerned for her as they have heard a loud noise erupt her vicinity. She laughs it off weakly as the scene switches to the dead end, where everything is scorched except the spot and area behind where the young man was standing.

Meanwhile, back in the Tokiwadai Dormitory, Kuroko prepares herself, as she narrates that it has been a month since she and Mikoto have been tied by the red string of fate (becoming roommates), and that they are going to celebrate the "anniversary", despite, as stated, that it has only been one month since that time. She takes a shower, puts on some lipstick, prepares some martinis (the non-alcoholic type), and puts on some fancy-looking lingerie. When Mikoto pears into her room, Kuroko tries to jump towards her. Of course, a color failure occurs afterwards, as Kuroko is shocked to see that Mikoto brought Saten and Uiharu along. After a knock on Kuroko's head, Uiharu and Saten are awed and overjoyed as they inspect the luxurious Tokiwadai Dormitory. Kuroko complains about how she had brought Saten and Uiharu to the dormitory, but Mikoto will have none of it, mentioning that they tagged along as she was shopping. Kuroko becomes suspicious of this, but Mikoto tells her that it's nothing. Mikoto then chats with Uiharu and Saten as they talk about their admiration for the fancy-pants Tokiwadai Dormitory. While still laying on the bed, Kuroko laments on how she has taken Uiharu and Saten in their special day. However, she starts imagining queer, apparently believing that Mikoto will announce their "apparent" relationship to them, and eventually convinces herself in a flurry of joyous convulsions. Of course, the others notice this too, though tells them to pay no heed. With that, Kuroko tells them to make themselves at home, to which they discover that Saten has already done, rummaging under one of the beds like she owns the place. She explains herself, and then takes out a box full of underwear. Saten shows in fullview a fancy underwear, and nearly everyone becomes flushed, except Kuroko who points out that its hers. Saten takes out increasingly risque underwear, to which Kuroko confirms it's hers, as well as the advantages of having one. Uiharu and Saten are shocked by this, and to feel at least normal, Saten once tries to get a glimpse of normal panties, that is to say, Uiharu's, much to her consternation. Kuroko says not to worry, as she has all sorts, and shows them off, such as an open bra babydoll, a laced teddy with garter belt, and a panty with cute frog critter on it. The both of them are relieved that even Kuroko could wear such a thing, however, it was soon revealed that it was Mikoto's, and Kuroko does not reply. Angry, Mikoto pulls on Kuroko's cheeks, demanding to know on how she has her underwear under her bed. Uiharu and Saten desperately try to calm Mikoto down, to which Uiharu gets an idea that she should show them their photo albums. To which, Mikoto could only acquiesce, showing off her album as she was a child. Seeing Mikoto's childish side surprises Saten, believing Mikoto to have been raised as a young lady and in the company of the elite. However, Mikoto tells her that she started off as a Level 1, surprising Saten, and shadows a frustrated look on her face. Uiharu then says it is Kuroko's turn to show her album, but tells her that she doesn't have one. Of course, Saten is a wiley girl and calls her bluff, somehow managing to find it herself, much to Kuroko's remonstrations. There in the album, they open it to find out it's filled with candid shots of Mikoto. While Uiharu and Saten becomes flushed again, Kuroko slowly walks towards the door, only to be once again punished by Mikoto. Like a thespian however, Kuroko dramatically asks if Mikoto knows what day it was. Mikoto ponders this, and comes to the obvious conclusion that it has been exactly one week today since they have become friends with Uiharu and Saten, making this a "septimaniversary", much to Kuroko's surprise.

While Mikoto, Saten, and Uiharu eat snacks and discuss the wonders of friendship that endured an entire week, Kuroko sulks in the corner. She comments on how there seems to be a difference in treatment by Mikoto between her and the other girls, and begins drinking her strange drink, a red bean beverage. Slowly, Kuroko chugs down the beverage very loudly, as the other girls converse, until Mikoto finally snaps at her being noisy. Kuroko does not respond well, derides the one week they have met, and reminds Mikoto on how it has been one month since they have been tied by the red string of fate, and starts crying like a child. Saten and Uiharu upon hearing this, believe that they shouldn't have come on this day. However, Mikoto calls out her name, and Kuroko stops her sobbing, but then Mikoto reveals the truth—she forced herself to become her roommate. Mikoto punishes Kuroko again, although the latter tries to explain herself, Mikoto does not want any of it. Kuroko however, escapes her punishing pull on her cheeks and tells her that it is all a matter of perspective, and states that she just wanted to have a modest celebration with her. Just then, their conversation is interrupted by the intercom. A delivery man has apparently delivered some "computer parts" to Shirai Kuroko, of Tokiwadai Dorm Room 208, much to Kuroko is a relief. However, much to her horror, Mikoto asks the delivery man who the sender was—Love and Herbs: Quality Aphrodisiacs, Ltd. Seeing what Kuroko intends to do in their modest celebrations, Mikoto confronts Kuroko, who intends to discipline her for her perverted streak, via electric shock. The dorm room explodes and the door is blown away, though, Kuroko manages to get away using her teleportation abilities. Kuroko laughs at her, as she reminds her of her ability. Mikoto, still angry, suddenly shows signs of mind-blasting fear. The thing speaks, it is the Dorm Mistress, telling cooly to Kuroko on how it is against the rules to use powers inside of the dorms. Suddenly, both Mikoto and Kuroko both turn into smiling syncophants, trying to appease the woman before them. Kuroko explains how there are extenuating circumstances that forced them to use their powers. The woman understands, but won't have any of it, and punishes Kuroko by snapping her neck, much to other girls' horror. The woman then tells Mikoto on how she must enforce the rules despite these circumstances, and Mikoto could only sheepishly agree.

The next day, Mikoto is seen cleaning something, and after much frustration, declares that it is impossible to clean it—their school swimming pool. Apparently, this was the punishment given to them given by the Dorm Supervisor While Mikoto keeps on complaining, Kuroko keeps sweeping on, all by her lonesome. Little did Mikoto know that she up to something sinister. She is apparently enjoying her private time Mikoto, who is now dripping sweat with sweat after a half a day's cleaning. As revenge for yesterday, Kuroko takes out a water container and tells her to have a sip from her specially made drink. Since Mikoto was not born yesterday, she points out that Kuroko must've put those "computer parts" from earlier. Kuroko's silence, proves Mikoto's suspicions. Suddenly, someone calls out to Kuroko, it's apparently her classmates, who are part of the swimming team, asking what she is doing here at the empty pool. Kuroko points out what she was here for, and begins conversing with them, meanwhile, Mikoto laments on how her underclassmen have larger "assets" than hers. Kuroko then introduces them to her oneesama, where the two are humbled in her presence. Kinuho reminds Mikoto of her heroic deed, when she saved her from a group of thugs, and thanks her for it. Kuroko is happy that her Oneesama is still the same as always, vigilant and brave. However, as she continues to watch the conversation between her Oneesama and her classmates, as well as from both Uiharu and Saten, a deja vu, as she aptly puts it. Kuroko is too shocked at the epiphany and just stands there. Kuroko tries to shake it off, until she sees Mikoto wholeheartedly taking Maaya's drinking container and drink from it. Kuroko notes the difference of treatment, and recalls on how Mikoto has ignored or violently turned down her approaches. Here, Kuroko begins to think that Mikoto is actually trying to shun her. Kuroko tries to think positive, and tells herself that with her teleportation abilities, she can be of use to her Oneesama in a myriad of ways. This is until Kinuho shows off her super useful for the situation Mikoto is in ability, Hydro Hand. With this, Kuroko silently falls into despair. The two underclassmen leave, needing to submit Kinuho's examination result to her teacher, with Maaya leaving her drinking bottle behind for Mikoto, and once again, she and Kuroko are left alone. Mikoto then starts talking to Kuroko, unaware of her feelings. Here, Kuroko keeps on replying with the same thing, which Mikoto finally catches after saying complete rubbish. Mikoto asks Kuroko what's the matter, though the latter tells her to pay no attention. Kuroko then starts tearing up as she says that she is of no use to her Oneesama and always causing her trouble. Mikoto could not respond, at a loss at what to do with a suddenly crying Kuroko.

In the meanwhile, in a nondescript family restaurant, Uiharu wonders if Mikoto has given "that" to her, which Saten notes that she wishes to see Mikoto give it to her, since they went out of their way to help her find it. Here, Uiharu reveals that it was Kuroko they were referring to, and references on her queer taste of underwear. However, Saten says that despite Kuroko's taste, it is the thought that counts, to which Uiharu agrees with a smile. Back with Mikoto, she draws a smile and calls out towards her crying underclassman-slash-roommate. Mikoto reminds Kuroko on what day it is: a month ago, on the evening after Kuroko barged into Mikoto's room and forced herself to be her roommate, and on the day after, they were forced to clean the cafeteria as punishment, just like what they are doing right now, and from then on and even until now, they are together. Mikoto points out that if there were any be an "anniversary" between them, it would be today and not the day before. Here, Mikoto hands Kuroko a gift, much to Kuroko's surprise. She takes it and unwraps it to discover a USA shirt, and with much joy, she tears up. Mikoto says that they'll always be together from now on. Kuroko asks if they would always be together (actually, she believes it to be together forever), to which Mikoto points out the obvious, and states that they are of course partners. Mikoto takes the two water bottles they had and drinks the contents down, of course Kuroko drank from her own spiked bottle. Refreshed, Mikoto opts to finish the work they have started, while Kuroko is in a really strange daze. Under the spell, Kuroko calls out to Mikoto, and tells her that it would be better to work while they are in their swimsuits. Mikoto replies that it would be a hassle to get them, however, Kuroko reveals that she has already taken care of it, much to Mikoto's rage, who throws and hits Kuroko in the face with the broom she is using. Kuroko points out however, unperturbed by the broom mark on her face, that lockers are not a match for her powers. Suddenly, Kuroko teleports behind Mikoto, and then teleports away her undergarments, much to her horror. Kuroko laments on how Mikoto has such childish taste. Mikoto, however, demands Kuroko to give them back, but is too embarrassed to do anything. Suddenly, Kuroko looks into the garment she just took and discovers that it matches, prompting her to run around the empty swimming pool, proclaiming that it matches. However, Mikoto finally snaps and attacks her. At the same time as this, both Kinuho and Maaya enter the area, having finished the exam and are ready to help them. However, what they discover is beyond their ken, as Kuroko, still under the daze of the aphrodisiac she took, takes in full the electric attacks Mikoto does on her. Seeing this, Kinuho and Maaya leave them to their own devices.

Adapted From[]

The second half of the episode is adapted from Toaru Kagaku no Railgun Manga Chapter 017, while the rest is anime-original.

Major Events[]

  • Mikoto meets Wannai Kinuho and Awatsuki Maaya
  • Kuroko and Mikoto celebrate their one month of being roommates.


New Characters[]


New Abilities[]


New Locations[]


  • This is the first time Touma appears, still retaining his memories before meeting Index, though he is not referred to by name. Mikoto will not refer to Touma's name until the Toaru Majutsu no Index PSP game, during a partial retelling of the events of the Toaru Majutsu no Index storyline, specifically, the prologue of the first episode of Index.
  • Despite Kuroko saying it their anniversary after she and Mikoto became roommates, only a month has passed, making this occassion technically a mensiversary. The term is abused several times in the episode.
  • Kuroko's album's name is called "Kuroko no (hi)Album Oneesama no HIMITSU". This would later be used as the title for a Toaru Kagaku no Railgun artbook featuring artwork of Mikoto by several artists, aptly called Kuroko no (hi)Album Oneesama no HIMITSU Kaizokuban, released on December 31, 2010.
  • The episode reveals a much different Dorm Supervisor to the one that was introduced in the 18th episode of the Toaru Majutsu no Index anime adaptation, complete with a different voice actress.
  • The names of the two members of the swimming club, Wannai Kinuho and Awatsuki Maaya was finally revealed in this episode. The manga has no mention of their names until this episode was aired.
  • Kuroko title drops the episode's name during the latter half of the episode.
  • Mikoto says "Zutto issho ni" after giving the shirt to Kuroko, which can either mean "always together" or "together forever", of course, Kuroko confuses what Mikoto meant with the phrase.
  • Despite the manga chapter that it adapted from is part of the Level Upper Arc, this is not the case for the anime.


  • A week has apparently passed since the first episode.
  • The episode references Kuroko and Mikoto becoming roommates, as well as the aftermaths of Kuroko forcing herself in doing so. However, the episode does not tell on how or why Kuroko became Mikoto's roommate, which is only slightly discussed in the 10th episode of Toaru Majutsu no Index, during Touma's visit to their dorm.

Cultural References[]

  • Kuroko references the Red String of Fate.
  • Saten references the Tokiwadai Dorm as being chic, a French word that means "smart" or "stylish".
  • Kuroko imagines an homage to the climactic farewell scene in Casablanca, with Mikoto in the role of Rick Blaine (Humphrey Bogart) and Kuroko in the role of Ilsa Lund (Ingrid Bergman). Despite Kuroko's imagination, they do not get together in the movie.
  • Mikoto makes a pun on Kuroko's name, which can be translated as "Black child".
  • Kuroko references the Déjà vu phenomenon.
  • A rabbit is seen on the USA shirt and shorts that Kuroko and Mikoto have respectively, this is due to the fact that the acronym of the United States of America, USA, means rabbit in Japanese.

Differences in Adaptation[]

  • In the manga, the reason why Mikoto amd Kuroko gets punished by the dorm supervisor is because they are past the curfew of the students entering the dorm, as they are finished getting interrogated by Anti-Skill on the recent AIM Burst incident.[1]
  • The flashback of Mikoto saving Wannai from Skill-Out thugs is cut in the adaptation [1]

Animation Trivia[]

  • The sound that Imagine Breaker produces whenever Touma negates something is replaced during this episode, and would be standard for the rest of the anime adaptation. It would only return during the second season of the Toaru Majutsu no Index anime.
  • The animation where Mikoto pulls on Kuroko's cheeks is reused several times in the episode.
  • The track "Skill-Out" from the second Toaru Kagaku no Railgun soundtrack, is played the during the Dorm Supervisor's appearance, despite the lack of presence of any Skill-Out.

Unanswered Questions[]

  • Who is exactly that dashing spiky-haired young man, and why is Mikoto chasing after and attacking him?
  • What exactly is the young man's power that stopped even Mikoto's power?
  • How did Mikoto save Wannai?


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


  • Kuroko: "Today is... Kuroko and Oneesama's anniversary. It was one month ago today... when were first tied with the red string of fate. It's unfortunate the goods I ordered didn't arrive... but today, Kuroko will... give one to her without fail. A present from my heart and soul. That's right, me, and all that I am!"
  • Saten and Uiharu: "Excuse... us!"―said as they entered Kuroko and Mikoto's room.
  • Mikoto: "Today is the one month anniversary of Kuroko and I being joined by the red string of fate. Kuroko and myself are two but joined as one. Uiharu-san, Saten-san, let's get along from now on too. Here's to your beautiful eyes."―Mikoto in Kuroko's imagination spot.
  • Saten: "Well you know, I just wanted to get back my everyday life. Seeing Uiharu's panties help me calm down."―said to Uiharu after discovering Kuroko's fancy underwear pile.
  • Kuroko: "Kuroko lives in the present. Rather than looking back to the past... or dreaming of the future, I want to gaze at this moment now! That's how I decided to live."―regarding why she doesn't have photoalbums.
  • Mikoto: "You definitely need to reflect on the now more than the past or the future!"―said to Kuroko.
  • Kuroko: "These red beans... They'll be discarded without anyone giving a second thought. I'm the same as these lonely beans!"―Kuroko comparing herself to red beans.
  • Mikoto: "I'm going to char you as black as your name."―said to Kuroko after discovering Kuroko's "computer parts".
  • Kuroko: "Now it's down to this, it's eat or be eaten. If you won't accept my love, then fight me!"―said to Mikoto.
  • Dorm Supervisor: "If I were to listen to every circumstance every time, I would not be able to uphold the rules of the dorm. Punishment must be exacted on those who break the rules. Don't you think, Misaka?"
  • Kuroko: "Even in summer, the winds of society can be cold."―said to Kinuho and Wannai
  • Kuroko: "I'm fine! I'm not suitable to be with Onee-sama. I always cause you trouble, and I can't help you... I'm not fit to stay by your side!"
  • Mikoto: "What should I do? This is so sudden I can't keep up."―regarding Kuroko suddenly crying.
  • Mikoto: "Of course, we go the same school, we live in the same room. Even if we wanted to, we couldn't be apart. After all, we're partners."―said to Kuroko.
  • Kuroko: "It matches! It matches! Matches, matches! It matches Oneesama's!"―regarding the shirt and shorts.
  • Maaya: "Let's pretend we didn't see anything."―said to Kinuho after seeing Kuroko and Mikoto's violent escapade.
  • Kuroko: "I'll never be disheartened. I'll stay by Onee-sama's side forever."


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