Tatsuki Mirei

Tatsuki Mirei (辰伎美麗) 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.

Appearance
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.

Personality
Tatsuki has exhibited a tendency for morbid remarks and voiced an apparent desire to dissect or stick things in peoples' brains. She also expressed a liking for Kumamori as a 'troll', and displayed similar behavior in addressing Iori with nicknames. She also supported prompt action and violence during the meeting between the election candidates. 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.

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

Tokiwadai Election Arc
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, as Shokuhou Misaki and Gaouin Tsukasa were working together to find evidence that would exonerate Hokaze Junko.

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.

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. 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.

Abilities
Tatsuki's ability allows her to pass through non-living physical objects. 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). 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. 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, with Tatsuki being impeded by carbon during the subsequent attack from Synthesize Grid.

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.

Tatsuki has experience (and an obsession) with dissection, mostly on non-living specimens. 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.