Kotomi Tsuda
Kotomi Ousai uniform



First appearance

Season 1, Episode 1 (anime)


3rd Year Junior High -> 1st Year



Personality Traits

Considerate and caring and highly curious and enthusiastic about adult matters


Ousai Academy


Member of Go Home Club, Member of Judo Club (for one day)


Asami Shimoda

Kotomi Tsuda (in Japanese Tsuda Kotomi) is the younger sister of Takatoshi Tsuda, who she affectionately calls "Taka-nii". Like her brother, she ultimately ends up attending Ousai Private Academy because of its proximity to home. She is considerate and caring toward others, but is curious and extremely (Takatoshi would say embarrassingly) enthusiastic about adult matters.

She is easily one of the most nonsensical characters in the series, and rivals Shino Amakusa, Aria Shichijō and possibly even Naruko Yokoshima as one of the most perverted.


During her initial appearances in the manga and throughout the first season of the anime, Kotomi was still in Junior High School. She later takes the entrance exam to Ousai Academy in Episode 12 of the anime and enters as a First Year student in the Season 1 OADs. It's hinted a big part of the reason she passed the entrance exam despite her admitted weakness in studying was because one of the teachers who interviewed her happened to be Naruko Yokoshima, who saw Kotomi as a kindred spirit.

Kotomi in her junior high uniform


Kotomi is a cute girl with long dark brown hair normally worn in twintails. She has big brown eyes and often has a big smile or grin on her face. She is more stylish than her brother, often wearing different outfits on her days off.

On a few occasions it has been observed that her breasts have grown quite a bit since entering high school, as she complained that her first uniform felt tight around her chest.


Kotomi is a bright and cheerful girl who makes friends easily. She is very popular among her classmates and has many friends, even among seniors like Mutsumi Mitsuba. She is naturally charming, to the point Suzu thought she could be an idol.
Kotomi closeup

Kotomi is bright and cheerful

However, Kotomi is also rather lazy and unmotivated, resulting in her being rather book-dumb and needing a lot of coaching from Takatoshi or Suzu to even keep up with Ousai's standards. In addition, she has a vivid imagination and often acts childishly, such as pretending she is the main character in a shounen anime.

Worse still is her shameless interest in adult matters, especially the kinkier forms of sex. Like Shino or Aria, she is well versed in common tropes found in galge (the term for dating simulation games like Love Plus or Amagami) as well as pornography. She doesn't seem to have any sense of time or place, happily talking about sexual-related matters anywhere and with anyone, much to the chagrin of Takatoshi or her best friend Toki.

She has also sometimes hinted at an attraction to Takatoshi, her own brother, but no one seems to be able to tell whether she's being serious about it or not. Takatoshi himself simply takes it in his stride.


Takatoshi Tsuda


Shino Amakusa

Aria Shichijō

Suzu Hagimura

Locations associated with Kotomi TsudaEdit


  • Her breasts are now larger than Shino's, something that irritates Shino greatly.
  • The "little sister who has a crush on her big brother" angle is a common theme among mangaka Ujiie Tozen's work. It is even the main theme of one of his previous works Imouto wa Shishunki (in Japanese 妹は思春期 literally meaning My Sister is in Puberty). Another character with an apparent crush on her older brother appears in his latest work Puchi Puchi Tantan Puchitantan (プチプチたんたん プチたんたん). Unlike Kotomi, however, these girls are dead serious about their interest in their older brothers. The sister in Imouto wa Shishunki often attempts to flirt with her brother (who ignores her) while the sister in Puchi etc. seems to act as though she and her brother are already married, even claiming he was her boyfriend (the brother laughs it off as her idea of a joke).