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Tobio Mami (飛緒 まみ Tobio Mami?) is a character introduced in Toaru Kagaku no Accelerator. She is the younger twin sister of Tobio Yumi.[1]


Mami has long red hair, and wears a yellow ribbon and an eye patch which she uses to hide a gaping hole where her eye should be.[1][2] This contrasts with her older twin sister who has a dark-colored ribbon on her head.[3] She wears a long dark hoodie and apparently no pants; revealing her bare legs.[1]


She is more vicious than her sister, taking down several Anti-Skill before coming face to face with her. In spite of this, she has warned her get out of her way first before she fought her.[4]


Mami and her sister moved into Academy City after their mother was chosen in a lottery. She ran a small a restaurant in School District 4, where the sisters helped her out. They later both went into the Power Curriculum Program, both of them manifesting the Volcanic Ball esper power at the exact same time. However, Mami later gets afflicted by a disease.[5]

Unlike her sister, Mami has had a "abnormal" upbringing somehow allowing her to train her powers to be more of an offensive and power version of her sister's and allowing her to keep using it more than a few times. It is implied that this abnormal upbringing led to her losing her left eye, necessitating in her wearing an eyepatch.[4]

Despite this, she became friends with Himegi Matsuri, letting her escape, wanting her to promise to her to leave the city. However, this is at the cost of her becoming "altered" and made a full member of Full Course.[5]


Toaru Kagaku no Accelerator

Nectar Arc

Main article: Nectar Arc
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Tobio is seen encountering her twin sister. Her twin criticizes her for her bad dictions. Yumi calls her by her given name. Mami says that she doesn't go by that name any more. The sisters argue. They fight Yumi realizes they are even and bets it all on a single attack. Tobio surprise her twin with a old attack.[4]


Tobio Mami using Volcanic Ball

Mami's ability is called Volcanic Ball (噴出球体ボルカニックボール Funshutsu Kyūtai (Borukanikku Bōru)?, lit. "Eruption Sphere"). It allows her to enclose the air currents into a sphere; compress and strengthen it; and then release it all at once.[4] Mami uses her ability in her hand can use it to propel herself over long distances. Her proficiency with the ability is greater than Tobio Yumi as she can use it in greater duration as well as use the compressed air currents like a cannon.[4] She can take a 2000m/s air current and give it further propulsion to create a powerful air drill.[6]



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Full Course
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Chef Tao Tobio Mami