The main character, a first-year transferee to Ousai, an erstwhile all-girls high school which has recently turned co-ed, because it is close to his neighborhood, only to be dragged into the position of Student Council Vice-President and representative for the nascent male student body.
Accidental Pervert: Whenever Shino or Aria catch him in unfortunate situations. The anime-only "Squid and Takatoshi" segments are built entirely around this.note Japanese thinks dried squid smells like semen.
Nice Guy: He's usually willing to help out wherever possible.
Noodle Incident: Whatever it was that he wrote in their school paper was enough to bring anyone who read it to tears. We never find out the contents of his essay, especially since the images shown while Shino and the others read it (something about a cat, a sailor, and a woman) had nothing to do with the actual essay's content. (Much to his frustrated bafflement.)
Twice Shy: He does seem at least a little attracted to Shino, but due to her perverse nature, and especially the bad publicity it would cause thanks to Ranko Hata (and who has spread a rumor they were already dating), he never makes a move on her.
Current Student Council President of Ousai Academy. On the surface she's the image of the straight-A student — serious, diligent and talented with most subjects. Behind that, however, she's quite the pervert.
A-Cup Angst: While she's definitely larger than A-Cup, she still wishes that she was bustier. This leads to situations where she takes sly digs at Aria (mentally or verbally, though mostly the former) or vice-versa. Her sly digs has found a new target in Uomi, after Shino found out that Uomi actually has sizable boobs.
The Ace: She's the top student of Ousai, is quite athletic, and it's occasionally shown that she is the go-to person for school related issues for which she always has good advice (Mitsuba, for example). Well, her perverted response is interpreted otherwise, anyway.
Can't Act Perverted Toward a Love Interest: Inverted. Shino is obviously interested in Tsuda and has no problem saying extremely perverted things around him. However, whenever Tsuda actually says something perverted (or when she thinks he's saying something perverted) directed at her, she gets extremely flustered. It is implied that on some occasions, she deliberately act perverted towards Tsuda to cover her real feelings for him.
Clingy Jealous Girl: While she never openly shows this attitude towards Takatoshi, the show strongly hints that she wouldn't take it well if he does date anyone else.
At one point in season 2 she asks if he has a girlfriend, and when he replies that he doesn't, she seems relieved and quietly mentions that she wouldn't know what to do if he did.
In episode 6 of season 2, she invites him to a fancy restaurant after becoming a pop idol. She then sees another woman approach him, despite having reserved the entire restaurant. He then introduces her to Shino as his girlfriend, who looks just like her, and is quite disturbed by that. In this example, it turns out she was just having a dream of what would have happened if she became an idol. However, it's likely she would still be quite upset at him if he does date anyone other than her.
In episode 9, one of Uomi's relatives marries one of Takatoshi's relatives, making them related by marriage. As a result, Uomi asks him to call her "onee-chan" (big sister), and she refers to him as "Taka-kun". When he tells Shino this, she makes a pouty face and grumbles. When Aria asks her why she looks upset all of a sudden, she claims it's because she had food in her mouth.
In episode 13 of season 2, she shows up at Takatoshi's house to drop off some food for him and Kotomi after hearing that their parents weren't going to be home that night. She's startled by Uomi being there as well, and insists on staying to make some more food too. And after Takatoshi says they should get going after dinner, Uomi assumed she was going to spend the night there. Shino, who was going to head home, then also immediately changes her mind and stays as well.
Expy: of Shiho from Idol No Akahon by the same mangaka. The difference is that Shino is a couple of years older and where Shiho uses an even mixture of intentional sexual talk and Freudian Slips, Shino is all-intentional all the time. It gets lampshaded when they meet in Shino's dream.
Green-Eyed Monster: She gets clearly jealous when Uomi uses her newfound closeness as Takatoshi's in-law to start aggressively flirting with him.
Teru Teru Bozu: She hangs one so that it doesn't rain the day before the pool opening day... and later turns it upside down when she learns that Hata will be taking pictures of her in a swimsuit.
Tsundere: Though less belligerent than most cases, it becomes more and more apparent as the story develops and she starts falling for Takatoshi. Officially lampshaded as of Chapter 177, in Dejima's head about the cast.
Twice Shy: She has a crush on Takatoshi, but due partly to her perverted nature, and the bad publicity it would cause thanks to Ranko Hata (who has already spread rumors she was dating him already), she never openly admits her feelings to him.
Uke: When Mitsuba mentions that the Judo Club is practicing Ukemi, Shino asks where the Seme is.
Shino: If there's an Uke, then there should be a Seme!
Shino's best friend and Student Council Secretary. Despite her affluent upbringing, she tends to follow her friend's mental processes.
The Ace: Not as prominently as Shino, but Aria is second only to her when it comes to grades, appears to be generally considered the more beautiful of the two, is a master calligrapher, and later revealed to have been a tennis player on the national level during junior high, before her breasts grew so big playing became painful. She's also probably the most outright perverted character in the series (while others, particularly Shino, occasionally make references more mainstream fetishes like whipping, Aria regularly takes them all to the realm of the utterly twisted and bizarre), but whether that's an achievement for her to be proud of is a matter of opinion...
Cloudcuckoolander: Spaced out at the bottom of the staircase before realizing that it wasn't an escalator, stood in front of the Student Council room thinking the doors were automatic sliding ones before Takatoshi asked her what she was doing, and actually thought her chest suddenly became lighter, when what actually happened was that she had bumped into Suzu.
Deadpan Snarker: Always smiles, but she gets especially cheery when she's making a dark or perverted joke (especially if it's a dig at someone else).
Too Kinky to Torture: The fact she didn't complain about the entire chastity belt thing should be obvious enough to say she is also into masochism. Gets into new heights in chapter 77, when she administered an enema at school... Given what this series is, it's definitively not for medical purposes.
Yamato Nadeshiko: If her perversions can be ignored, she would be a classical example of this.
Tsuda tells the girls to keep their watchful eyes at a distance while he works on his article. Aria then suggests that they do the staring like creepy stalkers from a partially-opened door, which creeps the living daylights out of Tsuda.
Aria did it again in Chapter 157.
Yaoi Fangirl: It is mentioned that she likes yaoi magazines and novels.
A first-year genius returning student and Student Council Treasurer. Despite being the more mentally mature girl in the cast, she has a huge complex regarding her short stature.
A-Cup Angst: Combined with being short, having the body of a little girl is a constant source of frustration for Suzu. She even has a dream sequence (used as a gag at one point) about hitting a growth spurt and becoming tall and busty.
Cannot Spit It Out: She does show signs of liking Takatoshi, but never acts on it much, aside from getting jealous when other girls try to get close to him, such as Uomi.
Catch Phrase: "And if I told you I'm a returning genius with an IQ of 180 who can speak 7 languages and make 10 digit calculations in my sleep, would you still say that I look like a little girl?!" (this is, of course, usually replied to with a "yes")
Clingy Jealous Girl: Like Shino, she is less than pleased when Uomi starts becoming closer to Takatoshi, such as the first half of episode 13/season 2.
Cuteness Proximity: This happens to her anytime Uomi is around, who simply can't resist hugging her.
Funbag Airbag: When she bumps into Aria, she works as this due to her size.
Tsundere: Aria refers to her as one. She even somehow convinces her to give the stereotypical 'It's not like I made these specially for you, it's just an obligation' type line... but Tsuda doesn't understand tsunderes, so he gets depressed.
Your Size May Vary: Her shortness tends to change depending on how much exaggeration of it is needed for a given joke. For comparison, her height generally seems to be between crotch to lower chest on Takatoshi.
Asleep in Class: Seems to have this problem, if her "New Year's resolution" of stopping that in Chapter 68 is of any indication.
Big Brother Attraction: She likes invokingBrother-Sister Incest (especially in the yonkoma), Season 1, Episode 12 has her admitting that she had an incestuous dream, and a strip in the yonkoma also mentions that she and Tsuda sometimes get mistaken for a couple, which she plays up. When her friend notes that it's sometimes hard to believe they're related because of their very different personalities in Chapter 43, Kotomi gets excited and interprets the comment as a possibility that they might be Not Blood Siblings. She also has no problem taking her clothes off in front of her brother◊ and once proudly mentioned to the other girls that he's also "impressive down there", which has him wondering as to when the hell she managed to sneak a peek. In the fourth OVA she becomes very, very pleased when Shino points out that she and Takatoshi being alone for the weekend while their parents are on a trip sounds like the setting of an eroge.
Book Dumb: Even more so than Takatoshi—she probably wouldn't have gotten into Ousai at all had she not been interviewed by Yokoshima.
Covert Pervert: Initially. Later she can be as openly perverted as Shino.
Ms Imagination: In Chapter 271, she actually attempted to established a club for "armoured fighting," because she found the armoured characters in video games cool. This is lampshaded in S2E10 in Dejima's imagination, seeing her as a "chuuniJK".
She also says "Shutter Chance!" whenever she sees a potential hot scoop (usually involving the student council).
Crazy-Prepared — Ranko, who brought a souped up digital camera, zoom lens, pan lens, and a bunch of other lenses, about a dozen bags of other equipment, a sound collector, a TV camera, and a motion capture camera, just to get a scoop of Shino during their trip to Kyoto. It was revealed that after Aria deleted the pictures that the identity card in the camera is a decoy.
She also carries a small bag containing an umbrella, a waterproof jacket, some food rations and a bottle for urinating. She takes her job really seriously.
Creepy Monotone: ...Which sets her apart from the other, hyperactive girls.
Deadpan Snarker: She can make these sorts of comments at times towards the student council.
Large Ham: A rather strange example as she carries the qualities of an Emotionless Girl, but is perfectly capable of being hammy.
Loophole Abuse: As per their agreement, she kept her mouth shut about finding Shino and Takatoshi spending the night together in an inn. She simply showed the disciplinary committee the pictures she took.
Twisting the Words: One of the things she likes doing is altering whatever statements she hears (usually from Takatoshi) to make it sound more perverted. It's apparently her belief as a member of the mass media.
Big Eater: Justified for being an action girl. A strip in Chapter 232 discussed that; she kept her tournament food expenses low by... fulfilling "big eater challenges" at restaurants. Yet, she's hardly fat, she burns it all off quickly.
Covert Pervert: Not even she's immune to it. In one gag, she's just returned from judo practice and is sweating profusely when Takatoshi asks her for help hanging something on the wall, requiring her to get close to him. When she blushes and says that she can't because she's covered in sweat, Takatoshi says he doesn't mind. Her eyes instantly light up and she excitedly asks "is that your feitsh?!"
This motif has been repeated a couple more times in recent strips, implying that body odor is, indeed, Mitsuba's fetish (or rather, she would like someone to have a fetish for her own).
The high-strung, androphobic head of the Disciplinary Committee and the Choir.
Covert Pervert: For all her prudishness, she immediately mistakes a perfectly innocent discussion on sleeping posture in chapter 120 as proof that the student council knows each other's sleeping postures because they have slept together. Shino and Aria call her out on this.
Ship Tease: Later chapters where she's gotten more used to Takatoshi's presence will also sometimes tease a possible infatuation with him. Later in the yonkoma, while she still avoids guys, she has no problem making physical contact with Takatoshi.
Expy: In-universe, of Shino, at least initially. Later appearances establish that she has quirks of her own and that she's more aggressive in trying to get close to Takatoshi.
First Name Basis: In Season 2, Episode 9, the relatives of Uomi and the Tsudas get married. She then starts calling Takatoshi "Taka-kun" and has him and Kotomi call her "Onee-chan," much to her obviousdelight.
Hidden Buxom: Her breasts seem around Shino's size but are actually much, much larger — much to Shino's jealousy.
Only One Name: We're not told whether Uomi is her first or last name.
Pretty Freeloaders: Later in the yonkoma she eventually uses her "we're relatives now" excuse to not only drop by Takatoshi's house frequently but also stay over. To the point that she even keeps some clothes in his home.
Running Gag: She has an obsession with hugging Suzu just so she can feel if she's wearing a bra or not, much to the latter's annoyance.
Shipper on Deck: Initially seems this way for Takatoshi/Shino, but she later expresses interest in and goes after him herself.
Shrinking Violet: According to her, she started as this, and still has the looks for this trope.
The Tease: Probably the most active one out of all the female characters. Unlike the others who largely sidestep the issue or just bury their feelings, such as Shino, Uomi makes it more obvious she's interested in Takatoshi. Unfortunately, due to the influence/saturation of being around the other perverted girls, her hints tend to fly over his head.