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Tatsuki Mirei (辰伎美麗 Tatsuki Mirei?) is a student of Tokiwadai Middle School who appears in Toaru Kagaku no Mental Out. She is a clique leader and one of the candidates for Tokiwadai's Student Council Election.


This section requires expansion
Personal features[1]

Tatsuki has dark-colored hair, slightly parted at the center of her forehead, wearing rectangular glasses and a light-colored headband. Being a Tokiwadai student, she wears the school's uniform.[1]


This section requires expansion
Fine tuning[1][2][3]

Tatsuki has exhibited a tendency for morbid remarks and voiced an apparent desire to dissect or stick things in peoples' brains.[1][2] She also expressed a liking for Kumamori as a 'troll', and displayed similar behavior in addressing Iori with nicknames.[1][2] She also supported prompt action and violence during the meeting between the election candidates.[1] Like most of the other election candidates, Tatsuki was not willing to give up on her bid for student council presidency and support another's bid for the sake of stopping another one of her rivals.[1]


Tatsuki's background is mostly unknown, but she was established as a clique leader by the time of the student council presidential election.[4][1] Her family runs a hospital in Academy City,[5] and she does in-service training there.[6]


Toaru Kagaku no Mental Out[]

Tokiwadai Election Arc[]

Main article: Tokiwadai Election Arc
This section requires expansion
Possible further expansion and fine-tuning[1][7][3][8]

Tatsuki attended the meeting Kamino held with the other election candidates (with the exception of Inubushi, who ignored Kamino's invitation) about potential cooperation and courses of actions in response to their two main rivals in the competition joining forces,[1] as Shokuhou Misaki and Gaouin Tsukasa were working together to find evidence that would exonerate Hokaze Junko.[9]

She participated in the joint attack the candidates launched against Shokuhou and Gaouin, being contacted by Iori Mashiro to change up their plan when she became impatient after the initial attacks by Tatsuki under Iori's directions missed.[2]

After Iori put an end to Mei and Kii's intervention, Tatsuki took the chance to launch an uncommanded attack against Shokuhou, resulting in Gaouin's arm being injured.[7] A panicking Iori expressed anger at Tatsuki acting on her own and causing a more serious injury than had been planned, but Tatsuki was unbothered and replied that she was bound to see some blood if she wanted to defeat them. When Shokuhou managed to deduce the nature of her ability, Tatsuki showed herself and had a brief conversation with Shokuhou, touching on the election and the Relic, actually using the time to build up an image of her targets' bodies in her head before resuming her attack.[3]


Attack on Shokuhou and Gaouin

Tatsuki's attack narrowing missing Shokuhou and Gaouin.

Tatsuki's ability allows her to pass through non-living physical objects.[2][3] As a student of Tokiwadai Middle School, it can be presumed to be at Level 3 or 4.

Using her ability, Tatsuki can rush forward at a person at high speed like a bullet to injure them (without damaging their clothes).[3] From observations of the attack and realization that it couldn't pass through the human body, Shokuhou speculated that if it did, Tatsuki's body would not survive and fall to pieces.[3] She further speculated from Tatsuki not passing through her swimsuit (100% cotton) or Shokuhou's leather bag, that she couldn't pass through either carbon or protein,[3][10] with Tatsuki being impeded by carbon during the subsequent attack from Synthesize Grid.[11]

When using this attack against Shokuhou and Gaouin while showing herself, Tatsuki 'dived' and 'surfaced' from the floor or ceiling, with a circular portal forming on the surface as she did so.[2][3]

Tatsuki has experience (and an obsession) with dissection,[1][3] mostly on non-living specimens.[3] When exposed and speaking with Shokuhou and Gaouin, she used time bought through conversation to observe their bodies (skeleton, muscle flow, height and build, fat distribution, organ placement etc) to draw up an accurate image of them in her mind, in order to aid her in tearing her targets apart.[3]



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Tokiwadai Middle School
Students (Current Year)
Misaka Shirai Kuroko Winter Clothing (Anime) Shokuhou Misaki in Winter Clothing (Anime) Hokaze Junko Winter Clothing (Anime) Kongou Mitsuko in Winter Clothing (Anime)
Misaka Mikoto[1] Shirai Kuroko Shokuhou Misaki[1] Hokaze Junko[1] Kongou Mitsuko
Awatsuki Maaya RailgunT (Anime) Wannai Kinuho RailgunT (Anime) Kirifu Megumi (Anime) Kobayashi Satori (Anime) Yumiya Iruka Color (Astral Buddy)
Awatsuki Maaya Wannai Kinuho Kirifu Megumi[1] Kobayashi Satori[1] Yumiya Iruka
Houjou Arei (Astral Buddy) Makigami Komaki (Astral Buddy) Maybe Natsumi Sakibasu Yuri (Navbox) Gaouin Tsukasa
Houjou Arei Makigami Komaki Natsumi Sakibasu Yuri Gaouin Tsukasa
Kamino Kokuchou Mayui Iori Mashiro Tatsuki Mirei Kumamori Tazuna
Kamino Kokuchou Mayui Iori Mashiro Tatsuki Mirei Kumamori Tazuna
Inubushi Glasses Judgment Girl - Commissioner (Mental Out) Mei (Anime) Kii (Anime) Resanerié Sadis Dialine
Inubushi Glasses Judgment Girl Mei Kii Resanerié Sadis Dialine[1]
Asato Kisa (Anime) Mibuki Kazan (Anime) Spy in Shokuhou Clique Otonari Hibiku
Asato Kisa[1] Mibuki Kazan[1] Nenohi Wakana Otonari Hibiku
AndouIkushimaInoriKinoshita HagoromoMatsuzai ShoukoSenbayashi KonomiTanaka MizuhoUmibe RyoukoUsukinu YasumiYonaki ReikaYamashiroYanagisakiin RondoYugure Kanaria
[1]: Student who is also present in Tokiwadai 1 year ago.
Students (1 Year Ago)
Kessai Kiyoshi (Navbox) Shinenkouji Rurikakesu Sha Tanshan Mikagami Nagisa Hasekura Reiri
Kessai Kiyoshi[C] Shin'enkouji Rurikakesu[G] Sha Danshan[C] Mikagami Nagisa[G] Hasekura Reiri[G]
Lily Ouyang Qian Lin Lihua Urui Aika Kazanin Tsukasa
Wu Lili Ouyang Qian Lin Lihua Urui Aika[G] Kazan'in Tsukasa[G]
Asakura Olivia Moa Kadosaka Rina Sukezawa Sena Enjou Kasumi Yasutoba Suika
Asakura Olivia Moa[G] Kadosaka Rina Sukezawa Sena Enjou Kasumi Yasutoba Suika[G]
Amano Ayane Unnamed Hasekura Clique Member 1 (Railgun Ch139) Unnamed Hasekura Clique Member 2 (Railgun Ch138) Unnamed Hasekura Clique Member 3 (Railgun Ch138) Ibotanokikouji Kaede
Amano Ayane[G] Satsuki Mahiru Soyogo Kato Asuwara Yui Ibotanokikouji Kaede[D][F]
For the unnamed clique members, see respective pages: Sha Clique, Mikagami Clique, and Hasekura Clique.
[C]: Student who is present in current year. / [D]: Deceased / [F]: Former student who haven't graduated but left school / [G]: Graduated
Students (2 Years Ago and Earlier)
Takebayashi Yayoi
Takebayashi Yayoi[D][F]
[D]: Deceased / [F]: Former student who haven't graduated but left school
Unabara (Mental Out Ch20, 6D+6F) Ryoukan Watanabe (Anime)
Director Unabara
Tokiwadai Dorm Supervisor Watanabe
v  e
Tokiwadai Election Candidates
Shokuhou Misaki (Mental Out) Gaouin Tsukasa Kamino Kokuchou Mayui
Shokuhou Misaki Gaouin Tsukasa Kamino Kokuchou Mayui
Iori Mashiro Inubushi Kumamori Tazuna Tatsuki Mirei
Iori Mashiro Inubushi Kumamori Tazuna Tatsuki Mirei