Okano has short brown hair that is the shortest amongst all of the girls in Class 3-E and she has brown eyes (light purple/pink eyes in the anime).
In her initial appearances, Okano was often shown to be serious with a relatively neutral expression. As the series goes on, she's later shown to also be playful in addition to being serious. She is also described as someone who acts before she thinks. Megu said that Okano is an honest person, but gets really stubborn when she's angry.
Okano has two brothers, both younger and older, meaning sports and muscle are what is talked about at home, potentially the reason she enjoys sports and gymnastics so much. Okano dropped to Class E from neglecting her studies due to club activities, causing her grades to drop rapidly.
Like her classmates, Okano was introduced in Chapter 1 however, unlike many of her classmates, Okano had yet to be properly introduced. Instead she has steadily been gaining more and more appearances as the series goes on with her first being in Chapter 24 when she was shown handing a towel to Maehara after he had been kicked to the ground by Tomoya Seo. This introduced her as one of the more serious characters of Class E. Her more playful side was highlighted in Chapter 86 when she was shown smiling when telling one of Shiro's men that she was still frustrated from the game of Cops and Robbers back in Chapter 81 and Chapter 82 and proceeded to take him out.
Okano finally receives the spotlight alongside Maehara in Chapter 158. The day before Valentine's Day, Okano accompanied Maehara after school. She had planned to give her chocolate early to avoid any embarrassment on the actual day but kept on hesitating until Maehara suddenly asked her to do karaoke with him. Okano happily accepted but was unaware that Maehara detected Korosensei spying on the two. After a while in a karaoke club, Okano planned to give her chocolate to Maehara. But the pair were then interrupted by Korosensei bursting in and being caught unaware by some of the students who answered Maehara's call. Having not been told of the plan, Okano throws her chocolate to Maehara and kicked him in the face before leaving in emotional anger. Okano spent the next day rebuffing Maehara's reconciliation attempts, still mad from the events of the previous night. At one point she even knocked out Nagisa who attempted to mediate the situation by throwing chair to him. Eventually Maehara outwits Okano by intentionally making her mad again and get her to kick him, having earlier replaced the hidden blade in her shoe with chocolate. Maehara admitted however that he would not have been in sync with her song choices at karaoke if he did not fancy her, briefly silencing Okano before getting violent once more when Maehara start mention about her silence.
Seven years after Graduation, Okano has become the Captain of Acrobat Performance Team by making her own club at the university she enrolled in, using back of the Class E mountain as her base of operations for training.
- Knifework: Okano excels in knifework and is considered one of the two best out of all the girls in Class 3-E. She was scored joint 4th in the class (along with Masayoshi Kimura, Meg Kataoka and Taiga Okajima) for Knife training from April to June.
- Agility: Okano has been noted for her incredible agility which is attributed to her being a former member of the school's gymnastics club. She is one of, if not the most, physically agile student of Class E which she attributes to her fighting making her excel in close-range combat.
- Skilled Acrobat: To be added
- Fighting Skills: Hinata excels in a close-range combat by utilizing her agility and gymnastics skills as her strong point which was her legs and her foot. On Assassination Island Arc, she manage to knock a Yakuza who was threatening Yuji unconscious with just a single kick to his face. She rarely using her hands on the fight as she prefer to use her foot in every fight. Her treasured possessions, Wrestling DVD also involves as inspiration for her fighting skills.
- Main article: Megu Kataoka
Her closest friend in Class E, they often spend time together when out of school. Okano calls her "Megu". Both of them are insecure about their own femininity and will spend time researching and figuring out what exactly it means to be "more feminine."
- Main article: Hiroto Maehara
Hiroto and Okano seem to have a good friendship and were paired up for Korosensei's Test of Courage and the Athletic Festival for the three-legged race. It has confirmed that she has romantic feelings for him, but she hasn't realized it, until proven in Chapter 158. Those close to her are able to see it, though. Maehara was the only one who knew every part of her personality and hobbies, such as her favorite song.
- Main article: Kaede Kayano
A good friend to Okano and is affectionately referred to as "Kayanochii" by her. According to a relationship chart, the two of them bonded over their insecurities about their physical appearances.
- Main article: Toka Yada
Yada is a member of her Field Trip group with whom she has good relations. She has mixed joy and envy towards her bust size. Okano refers to her as "Yadacchi".
- "I'm still frustrated from being hunted by Karasuma-sensei, so for this cops and robbers, you guys are the robbers, okay?"
- (Season 2, Episode 1) "Fine whatever, huge boobs we can work with. Not like we have a choice and bust size doesn't really matter that much anyway."
- Hinata's surname Okano means "ridge, hill" (岡) (oka) and "field, wilderness" (野) (no).
- Okano was called "Amazing Monkey" in class 3-E training using code names and the one who wrote her codename was Hiroto Maehara.
- Okano's best subject is Physical Education, while her worst one is English.
- Okano's profile notes her personality to be "brash and clumsy".
- Okano's past club before joining Class E was the Gymnastics club.
- Okano's hobby is to easily complete Karasuma's training lessons.
- Okano's most treasured possessions are Wrestling DVDs.
- Okano's favourite food is grilled chicken from family restaurants.
- Okano prefers bentos over snacks.
- Out of all the class that mainly uses fists as main weapon to fight at close combat, Okano use kicks as a main weapon as she is the only one that has an anti-sensei knife hidden on her shoes.
- Okano's special skill is the 540 Tornado Kick.
- During the Civil War, Okano and Masayoshi Kimura were both eliminated after swinging into a net trap.
- Okano's grades overall were:
- 1st Semester Mid-Terms: 278 points (138th place)
- 1st Semester End-of-Terms: 353 points (85th place)
- 2nd Semester Mid-Terms: 334 points (108th place)
- In the tankobon extras, Okano's statistics were listed as:
- Physical strength: 4
- Mobility: 5
- Close-range assassination: 4
- Long-range assassination: 1.5
- Academic ability: 2
- Characteristic skill: 4.5 (four-directional attacks)
- Assassination Classroom Manga: Chapter 24, Page 15
- Assassination Classroom Manga: Chapter 86, Page 10
|Kunugigaoka Junior High School|
|Faculty||Korosensei • Tadaomi Karasuma • Irina Jelavić • Aguri Yukimura|
|Students||Masayoshi Kimura • Hinano Kurahashi • Yuma Isogai • Hinata Okano • Hiroto Maehara • Meg Kataoka • Kotaro Takebayashi • Toka Yada • Koki Mimura • Rio Nakamura • Nagisa Shiota • Kaede Kayano • Taisei Yoshida • Yukiko Kanzaki • Taiga Okajima • Rinka Hayami • Tomohito Sugino • Yuzuki Fuwa • Takuya Muramatsu • Kirara Hazama • Ryunosuke Chiba • Manami Okuda • Sosuke Sugaya • Sumire Hara • Ryōma Terasaka • Karma Akabane • Itona Horibe • Ritsu|
|Faculty||Gakuho Asano • Kiyoshi Terai|
|Students||Tomoya Seo • Teppei Araki • Natsuhiko Koyama • Ren Sakakibara • Gakushu Asano • Kaho Tsuchiya • Kazutaka Shindō • Kokona Tagawa • Nobuta Tanaka • Chousuke Takada|