Rio Nakamura

Rio Nakamura is a student in Korosensei's Class 3-E of Kunugigaoka Junior High School. She was a former elementary school genius but felt lonely and longed to be normal. When she got to middle school, she began shirking off her studies which landed her in Class 3-E.

Appearance
Rio has long, straight strawberry blonde hair (a darker blonde in the OVA), parted in the middle and worn swept behind her shoulders, and she has aqua blue eyes (sometimes appearing as light gray) with notably long eyelashes. The colors of her hair and eyes give her the appearance of a stereotypical Caucasian girl, despite the fact that she is Japanese, though her hair does appear to be dyed, as in a flashback she appears with a darker shade.

She wears the Kunugigaoka school uniform with the assigned pale yellow sweater, rather than the gray blazer.

Rio is described as the “cool and gorgeous girl” of Class 3-E.

Personality
A girl whose sleaziness can put even Class E’s perverted genie Okajima to shame, she also shows the keen intellect of someone known as a former child prodigy. At the same time, she also greatly enjoys doing teasing others, displaying a genius-level gift for it. She has a nose for finding people to mess with.

Rio is also a friendly, energetic girl and somewhat of a trickster. Her favorite victim, along Karma is Nagisa. She's playful, has a bit of a dirty mind, and has been noted to be rather intelligent. She claims she was originally a serious person, something that would prove to be true when she disagreed with Nagisa's proposition to save Korosensei and continue to kill him.

Despite her eccentric nature, she has the ability to see the bigger picture and hides how she really feels, but she cares about Class E more than anyone. She also felt responsible for the bond between the class and Koro-sensei.

On one hand, she can play the role of Class 3-E's resident mischief chick. On the other hand, when the situation calls for it she can be quite straightforward. Even Terasaka started to wonder which between the two of them is the more outrageous kid in class.

Plot
Like the majority of her classmates, Rio debuted in the first chapter; however, she didn't originally get spotlighted until the first Finals Arc (Chapters 51-53) where she and Nagisa were the main rivals to Tomoya Seo in English. Before that, she was introduced during Chapter 18 where she was trying to peek in on Korosensei.

She gets another spotlight in Chapter 111, where she reveals her past as a gifted, but lonely elementary school student. She was the top student, but felt lonely and unsatisfied and wondered how would it be feel to be a normal student. Because of how gifted she was, the other kids don’t chat with her about the tests. Putting it another way, her superiority, her “difference”, makes it hard for others to approach and understand her. Since then, she decided to "be stupid", by shirking off her studies and acting playfully. In the process, she completely forgot how to study and how take tests, prompting her fall into Class E.

Bad behaviour like dress code violations, using profane language with her teachers, and insufficient attendance is what also lands her in Class E. She expresses her gratitude to Korosensei for providing her with a place where she can both study and do "stupid things" along with her friends.

Rio contributes to Class 3-E's school festival in gathering the ingredients for their restaurant. However upon seeing Yuji Norita recognising Nagisa from the summer holidays, she quickly changes Nagisa's pants for her skirt and has him try to swindle money from the unsuspecting Yuji. Eventually Nagisa confesses that he is not a girl as Yuji had thought, Rio even covertly suggesting to Nagisa to "show it to him".

At the end of Chapter 142, when Nagisa proposes to find a way to save Korosensei instead of assassinating him, Rio is the first to speak against it. She cites the bond between assassin and target the the very reason why she wants to continue killing their teacher. Her disagreement eventually causes the class to split into either saving or killing Korosensei, prompting him to settle the dispute by having the two factions play a paintball match against each other. Rio joins the red (kill) team and acts as second-in-command to Karma Akabane.

When the strength of both sides have been cut in half, Rio heads to Ryoma's position and lie in wait until the blue team attacks to capture their flag. She reiterates her resolve to kill Korosensei, earning Terasaka's subtle praise. When the surviving blue team attack, Rio's group raced for the flag but but were ambushed from behind by Nagisa, thus eliminating her from the battle. She later watches Nagisa and Karma's brutal fight, which Nagisa eventually wins when Karma surrenders after being caught in a chokehold. Despite her earlier disagreement, Rio sees how both sides fought their very best and as such decides that Nagisa's side won fair and square. She even made up to Nagisa by playfully pinching him on the cheek.

Rio makes another major appearance during Valentines' Day, conspiring with Karma to teasing Kaede about her affections for Nagisa. The pair help Kaede build up her courage by taking her to spy on other couples throughout the mountain. Rio and Karma both watched Kaede present her chocolate to Nagisa and afterwards Rio indirectly confessed to Karma that she will not act on her own feelings for Nagisa for Kaede's sake.

She makes an appearance when the students try to save Korosensei from the government’s hands where Korosensei notes she moved gracefully during battle. She then reveals she had brought Korosensei a cake to celebrate his birthday and the entire class sings him happy birthday. They are interrupted by Shiro and the God of Death’s arrival.

After the fight, Korosensei asks Rio to feed him the cake in order to help save Kayano to which Nakamura deadpans it had been covered in dirt due to the fight that occurred but nonetheless gives the cake to Korosensei.

In the ending, she bravely tries to face Koro-sensei's impending death with a smile during his final roll call; that facade soon crumbles in tears after he is gone for good.

Seven years after graduation, Rio was seen in England chattering with some college student and laughing together on a bridge near Big Ben Parliament during her exchange program.

After graduating college, she became a freelance interpreter and aims to work at the Ministry of Foreign Affairs.

Her dirty jokes garner a lot of grand reactions even when she's studying abroad in the west, and fitting there was a great success for Rio. She started working as a sharp and witty interpreter, aiming to establish her career with the personal connections she'd established.

Abilities
Marksmanship: Rio is ranked 4th for marksmanship, girls' side. She scored 79/200 in a test in June, giving her the 7th best marksmanship in Class 3-E.

English: Rio has a mastery over this subject and apparently the language itself and she's ranked 1st in the school for it.

Intelligence: Rio, despite her whimsical personality, is actually one of the smartest people in Class E, second only to Karma. This stems from her past as a genius elementary school student and though she forgot how to study, she hasn't lost her own wit and guile.

Technology: Rio was ranked 3rd for technology in Class 3-E by Korosensei, stating she was able to dissemble a radio within seconds but it was a shame she found reassembling it boring.

Night vision: She was ranked 4th by Karasuma in the students’ night vision abilities.

Nagisa Shiota
Rio sits beside Nagisa enjoys messing with him and harassing him. She gets a kick out of playing on his androgynous appearance and according to the tankobon extra this is one of her hobbies. Despite that, the two are good friends and Nagisa doesn't pay much mind to her teasing.

In Chapter 116, Rio apologizes to Nagisa when she found out that the reason he kept his hair long was because of his mother's oppression, and says that she won't tease him about it anymore. However, the moment Yuji appeared, Rio breaks her promise and cross-dressed Nagisa.

It is hinted that she has a crush on Nagisa, indicated when she made an indirect confession in front of Karma, but gave up as soon as Kayano made her move.

Karma Akabane
For most of the series, Karma and Rio were not shown to be interacting much together except for a few snippets where they tease Nagisa together. Their first well-known interaction was during the civil war when the two shared a common ground in opposing Nagisa's suggestion to save him. During that time, she acted as Karma's second-in-command.

As the two most intelligent students of Class 3-E, the pair are of the same mind and it is even said that they can finish each other's thought. The two also share the pleasure of playfully teasing Nagisa.

They are also described as conversation partners with matching mentalities, and since their breadth of words and knowledge are similar, their topics can jump from candy to world economics in seconds.

Hinano Kurahashi
Though they aren’t often seen together, the two of them have bonded over bejeweling their knife sheaths. The two of them also seem to have their airheaded moments together, as they casually were showing them off during a school assembly, much to Karasuma’s dismay.

When Hinano tells the girls that she has a crush on Karasuma, Rio remarks by telling her no girl in 3-E does not have a thing for him. The two are also shown battling each other with knives during one of 3-E’s PE lessons before Takaoka’s arrival.

Yuzuki Fuwa
Frequently peeks at the shonen manga over Fuwa’s shoulder, and often feels the progress of the characters are moving towards a sloppy direction. The character relationships that Fuwa favours run in complete counter to Nakamura’s, so Rio feels flustered when they become ruined to her.

Sumire Hara
At a glance the two have completely different styles, yet the quick-thinking Nakamura and the considerably mature Hara actually have a lot of common topics which they often discuss, their relationship has a joyful atmosphere to it. Rio refers to her as "Hara-chan".

Ryūnosuke Chiba
She’s actually fond of music. Because she often listens to Western songs, she has some differences in opinion with Chiba, who prefers Japanese Punk. Rather than European, she favours the more exciting nature of American music.

Okajima Taiga
Since she has a lot of guy friends, she is not repulsed by dirty talk. To the point that she and Okajima together may set the mood even more sleazy. Okajima comments that she's the first girl to make him feel like he might lose to her in terms of sleaziness.

Trivia

 * Her favorite subject is English while her worst is Civics.
 * Irina notes that unlike her school uniform, she favors wearing pants for streetwear. Also, her skill at dressing down so that her clothes are fashionable without being particularly casual was something to be noted.
 * Her past club before joining the Class E was Amateur Radio Club. Back when she was still in the club, toying with the boring men who turn up before going home was a daily lesson for her.
 * She is the president of the Crossdressing Nagisa Appreciation Club.
 * Her favorite food is Pizza.
 * She hates boring men.
 * Her hobbies are hanging out with friends, dirty jokes and sexually harassing Nagisa.
 * She prefers snacks over bentos.
 * Her older brother is in university; he has a lot of refined interests but has a sister complex.
 * Her father is a translator and her mother formerly was an advertisement model.
 * She wants to be a diplomat or an interpreter (presumably due to her English skills) in the future.
 * In the tankobon extras it was revealed that her current nickname is "Old Mannish Middle Schooler" while her past one was "Elementary School Genius."
 * She was paired with Sōsuke Sugaya in Nuru-Nuru Test of Courage in Chapter 74.
 * She is seen trolling Yada and Kayano on the girls’ group chat in one of the tankobon extras.
 * Her profile photo online is Nagisa wearing a skirt.
 * Her current hair color was revealed to be dyed as shown in a flashback in Chapter 111.
 * When she was in first grade, she got 100% on 6th grade tests.
 * Contrary to her status as a "gifted girl" when she was in kindergarten, she even got reported on TV.
 * Despite the way she acts, whenever a perverted situation happens, she's shown to be completely disgusted. However, she playfully notes that Taiga has a small penis while all the other girls were enraged at his flashing at the beach during Summer Camp.
 * She says she hates looking at pictures of herself because she doesn't like her small eyes.
 * During the Civil War, she was eliminated along with Ryoma, Taisei and Takuya after Nagisa ambushed and shot all 4 of them.
 * She placed 11th overall during the first semester final exams.
 * She was ranked 3rd overall in the final semester exams with a score of 469, after Karma(500) and Asano Gakushuu(497).
 * She is known as the 2nd smartest student in Class-3E.
 * Her and Gakushū Asano's English voice actors are married in real life.
 * In Karasuma's Assassination Aptitude (out of 6) her statistics were:
 * Strategy/Planning: 5
 * Commanding/Leadership: 3
 * Execution (Ability to carry out plans): 4
 * Technique (Traps, weapons, preparations, etc): 3
 * Scouting/Intelligence Gathering: 4
 * Politics/Negotiations: 4
 * In the tankobon extras, her statistics were listed as:
 * Physical strength: 3
 * Mobility: 3.5
 * Close-range assassination: 3.5
 * Long-range assassination: 3
 * Academic ability: 5
 * Characteristic skill: 4.5 (wasting talent)
 * Her bug in Koro Q is "Status Switcher" (Koro Q manga Chapter 18)