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Gaouin Tsukasa (雅王院司 Gaōin Tsukasa?) is a student of Tokiwadai Middle School who appears in Toaru Kagaku no Mental Out. She is the incumbent Vice President of Tokiwadai's Student Council[2] and leads the Gaouin Clique, the second largest at the school.[4]


She has shoulder length black hair, which she ties into two pigtails. Her eyes have concentric circles in them.

Apart from the standard Tokiwadai uniform, she wears one glove on her left hand. She wears stockings or a pantyhose with her uniform. She is also seen holding a pocket watch with a lion emblem.[2]


She's prideful and is easily willing to go toe-to-toe against Shokuhou Misaki herself. She's a stickler for efficiency and this is shown by her using a silver pocket watch to quickly criticize students asking for her help and feedback. The silver pocket watch itself is a sign of her influence as when she raises it means she is taking requests and she is immediately approached by her followers. She even proclaims that it is a sign of her bond with her followers.[2] She idolizes precious relationships of Tokiwadai girls, but she does not want to intimate contact with other girls like Shirai Kuroko. She envies Tokiwadai from the bottom of her heart for being preciousness and even wish to be Tokiwadai itself.[1]

Due to how old-fashioned it looks, Misaki calls Tsukasa as someone who is a "chuuni" (中二, lit. "middle-school second-year"), someone having chuunibyou, and that she lacks real confidence and uses props to hide behind.[2]

She is bothered by her short height, so she has dreams of being 168cm or taller.[4]


As the start of the story, Tsukasa begins her election campaign to become the next head of the Tokiwadai Student Council. She leads her own clique and uses to help her win. She plans to break up all the cliques in the school.[2]

She has an extremely broad range of friends and a student council maid as her aide.[4]


Toaru Kagaku no Mental Out[]

Tokiwadai Election Arc[]

Main article: Tokiwadai Election Arc
This section requires expansion
General expansion/fine-tuning[4]

The day before the arc's main events in October, Gaouin had observed Misaka Mikoto down, due to losing her Gekota strap when two people fought over getting her support for their respective election campaigns, and had searched for it in the forest behind the school, eventually finding and returning it to her,[5] leading Mikoto to support her own effort in return.[6][5]

The next day, Gaouin and her supporters got into a dispute with Shokuhou Misaki and her clique, leading Gaouin to issue a challenge for Shokuhou to compete against her in the student council presidential election, which the clique pushed the reluctant Shokuhou into accepting, and voiced her intent to disband all cliques if she was elected president.[2] She would later visit the clique, who had had their usual room sneakily taken from them, to explain the rules behind the election, with another individual revealing Mikoto's support for Gaouin over the announcement system.[6]

Not long afterwards, when Hokaze Junko was accused of threatening and coercing a member of the Kamino clique, Gaouin decided to help Shokuhou find evidence that would exonerate her, the two forming a shaky, temporary alliance to that end, searching independently from their cliques.[7][1] The prospect of their two main rivals joining forces led to Iori Mashiro and Kamino arranging a meeting with the other election candidates and forming an alliance themselves with intent to forcibly take them out of the running,[8] something Gaouin did not anticipate.[9]

While the two were searching the vacant Building 3, they were ambushed and trapped in the building, coming under attack from their hidden rivals. During the attack, Gaouin avoided numerous attacks, leading the attacking clique leaders to wonder if a predictive ability was at work, but eventually sustained a severe injury to her arm when pushing Shokuhou out of the way of Tatsuki Mirei's attack.[10][11][9][12]


Gaouin's Ability (Mental Out Ch15)

Gaouin using her power to scatter Synthesize Grid's nanometal particles by deflecting the hostility carried through them.

Gaouin's ability is Reflex Answer (感応反射リフレックスアンサー Kan'nō Hansha (Rifurekkusuansā)?), a psychological-type power which allows her to receive and reflect thoughts. It can be used to reflexively reply a question, but the answers are reliant on her own knowledge, experience, and resourcefulness.[4] According to Gaouin, it is capable of blocking Mental Out even at full strength.[13] During an attack from the Synthesize Grid, Gaouin scattered remotely controlled nanometal particles, which were conducting part of the attack on auto-pilot, by deflecting the hostility carried through them.[13]

As a student of Tokiwadai Middle School, it can be presumed to be at Level 3 or 4.

Character Art Designs[]



Gaouin Tsukasa and her watch

Gaouin with her watch.

  • She has a devastatingly bad sense of direction.[1][4]
  • Her grandfather's friend is apparently related to the company which produced Gekota.[5]
  • She respects her grandfather and is quite the grandpa's girl.[4]
  • Unlike other Tokiwadai Student Council candidates,[8] Gaouin lacks an animal character in her name, though she may have an animal associated with her. Gaou (ガオー Gaō?, alt. Gao, ガオ) is onomatopoeia equivalent to a roar, a sound typically made by a lion or tiger, and the emblem on her pocket watch is a lion.[2][4]



v  e
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