Fukiyose Seiri

Fukiyose Seiri (吹寄 制理) is Touma's classmate, Aisa's best friend, and often takes up roles of the class representative even though Aogami is the class representative.

Appearance
Seiri is a young girl in her mid-teens with a slender, yet solid build. Like Kazakiri Hyouka, she is considerably well-endowed for her age.

Personality
She dislikes people (namely Touma) who give up on their life and blame it on bad luck. It is debatable if she is tsundere towards Touma or only dislikes him because of his attitude towards life and school in general, but she does have a sort of friendly relationship with him, even sometimes playing a role of tsukkomi for Touma who acts as the boke. She is mentioned as the girl who is "pretty but lacks sex appeal." Her nickname is "The iron wall girl", She is a health-product freak and is frequently ordering different health products from television shopping channels. Her abilities have yet to be revealed.

Fukiyose holds the unusual privilege of being the only girl that walked into Touma while he was changing instead of the other way around (albeit, Touma has walked into Fukiyose changing as well in another certain occasion). Even though in that opportunity Kamijo was "the victim" Fukiyose chose to beat him up in response to her embarrassment regardless of that.

She has been shown to posses several skills, being able to throw fast pitches and fork balls when playing baseball, being a fast runner, and being able to perform both Aikido and Judo throws quite swiftly. All of this broad knowledge in several disciplines comes from self training and self exercise following advices on whats healthy to your own body.

Plot (Toaru Majutsu no Index)
She was a member of the committee of coordination for the schools and did her best to make sure the students enjoyed the games, but later during one of those games, she was almost accidentally killed by one of Oriana Thomson's flashcards which dried off her life energy. She was saved by Touma who dispelled its effects. Thinking that the cause of her collapse was a sunstroke, she is later seen recovering with help of Heaven Canceler, in the hospital where Touma usually ends up after getting hurt. After checking out of the hospital, she got a call from Tsukiyomi Komoe about Aisa being attacked and was shocked to hear it, although Komoe later told her that Aisa would be alright. Later, she would run into Touma while he was undressing, and she beat him up for it even though he was the victim. The two would later argue about that incident while they were going to check on Aisa.

After her introduction she becomes a pseudo regular member of the cast, more often than not playing the tsukkomi that hits the boke whenever Touma, Aogami and / or Tsuchimikado do something too stupid during class (this happens quite often). She can easily floor any of the three and the three of them at the same time with a single strike each, and Touma has commended the big strength of her trademark attack, a strong headbutt of which Touma is usually on the receiving end

Quotes

 * (Said after seeing Touma collapsed, Volume 9) “I hate those who use misfortune as an excuse to live life so sloppily. Once you look so lethargic, everyone else will lose their motivation as well. So you better buck up for everyone’s sake.”
 * (Said after being asked why she floored the Delta Force, Volume 12) "For the sake of world Peace!"
 * (Said to a Oyafune Sensei, Volume 14) “I was just trying to get these idiots to shut up!! Why did I have to be dragged down here along with them!?”
 * (Said to Kamiyo Touma, Volume 14) “And before you ask: I won’t let you see my notes.”

Trivia

 * Fukiyose, Aogami, Tsuchimikado and Touma are considered the ones with the best motor skills within the class, the source for these thoughts is that they are always stirring up trouble.
 * All of the members of the the idiot trio are quite apt when it comes to brawling, however Fukiyose always manages to take them out with a single strike. While Seiri isn't implied to be weak, this probably stems from the fact that the trio doesn't fight back or isn't ready to fight back while they are on "baka mode".