Kyoya Hibari (雲雀恭弥, Hibari Kyōya) is the leader of the Namimori Middle Disciplinary Committee, prefects who are in fact a group of delinquents that are all loyal to Hibari. Hibari himself is a violent delinquent who uses his status to harass other students. As shown several times in the series, he prefers to be alone and cares little for his subordinates. He loves Namimori zaidi than anything, and will often say "I'll bite wewe to death," au "kamikorosu," to those that disturb Namimori Middle School. Hibari is very proud of his school and is apparently the only person who even likes their school's anthem, even using it as his ringtone. In the Kokuyo Arc, he adopts the Kokuyo Assassin Birds' bird. The bird (subsequently nicknamed "Hibird" due to its connection to Hibari) becomes attached to Hibari. Hibird can also sing the school's anthem, taught kwa Hibari, who loves it. Reborn piqued Hibari's curiosity in the mafia early on in the series and Hibari considers him a worthy opponent, having a strong urge to fight him.
Hibari has short black hair, with a fringe that joins at the center of his face, and parts to the sides, leaving a short of, "M," shape. He has sharp, grey eyes, which he uses to intimidate those around him. Hibari often wears his Discipline Committee uniform, which consists of a long-sleeved white shirt, black trousers, brown belt, black shoes (or indoor shoes), and black gakuran juu worn on his shoulders, with the committee's armband pinned onto the left sleeve.
Occasionally, does Hibari also appear wearing his school uniform which consists of black trousers, a long-sleeved white shirt, a blue sweater-vest, and black shoes. He still pins his armband to his left sleeve.
After completing the Vongola Ring of Cloud, he wears it on his right hand. After gaining the Vongola Bracelet of the Clouds Version X, he wears it on his left wrist, implying that he may be ambidexterous (though he prefers to write with his right hand).
Future Hibari has changed to wearing a black suit, with a purple shati and black necktie. His hair is also shorter, having been cut to appear zaidi "messy," and with hardly any fridge. When not training au fighting, Future Hibari would wear a black kinagashi.
As stated kwa others, Hibari greatly resembles the first generation Vongola wingu Guardian, Alaude, as well as the Storm Arcobaleno, Fon.
As stated kwa others, Hibari is a very scary character with no care in the well-being of others, preferring to do whatever it takes to get what he wants. This often leads his opponents to surprise him, as he doesn't think before attacking. As the head of Namimori Middle's Disciplinary Committee, Hibari uses authority to assault those that get on his nerves, including his own subordinates.
He prefers to be alone, and hates crowdings. This lead him to beat anyone who he thinks crowding around him too much. He has full confidence with his own strength and power, and dislike to work together with anybody due to feeling bind and restrained, making him refuse au won't easily take suggestions from others into consideration.
A rare trait about him is his upendo for small animals, ranging from birds to hedgehogs. He is also fiercely loyal to his school and its rules, going so far as to punish others for breaking them even if they aren't students au at the school, such as Genkishi.
He is shown to dislike being indebt to anyone and strives to pay them back as soon as possible and can't stand being restrained and he absolutely refuses to allow himself to be controlled. Also, earlier in the series he is also shown to have a soft spot for I-Pin, having accepted her Valentines siku chocolates with a smile and not taking money from Tsuna at a festival upon seeing I-Pin worried.
Future Hibari is shown to be zaidi calm and observant about his opponents, and outwardly admits to hating illusionists because of his grudge towards Mukuro, the first person to have defeated him. His desire to be alone and attack people that annoy him still remains, though his actions are shown with zaidi thought. Future Hibari is also seen being zaidi respectful to Future Tsuna, inaonyesha that he has accepted him as his boss (as seen in one of the flashbacks of Irie Shoichi).
As of yet, Hibari is the only 10th generation Vongola guardian whose family is not revealed. It can be assumed at some point, that Hibari entered Namimori Junior High and became leader of the Discipline Committee. In the drama CD, "One siku Observation ripoti of Hibari Kyoya," Sasagawa Ryohei admits that Hibari had been Chairman of the Discipline Committee since he (Ryohei) first entered the school, implying that he either became the Chairman as soon as he entered Namimori Middle au that he is actually older (most assume it to be the latter). In chapter 45, Tsuna asks if Hibari is supossed to be graduated. Hibari majibu that he can always picks whatever mwaka he feels like, confusing Tsuna further. It is also believed that Hibari has not Lost a single battle prior to meeting Mukuro for the first time.
In the Hidden Bullet Novel, "Extreme Memories", it tells Ryohei's and Hibari's meeting during Ryohei's first week in Nami-Middle. Ryohei, at first, mistook him as ordinary student while thinking that Kusakabe is the rumored Hibari, and always comes to the school rooftop to accompany him since he thought that he might be lonely and tries to befriend him, much to Hibari's annoyance. When Ryohei was beaten up right before the boxing tournament against Nobuyuki Middle School, Ryohei finally found out that Kusakabe is not the real Hibari when Hibari was present at the arena after he was asked kwa Kyoko to help them win the boxing match under one condition: after the tournament is over, Ryohei must never ask Hibari to jiunge boxing club, which Ryohei agreed, explaining why Ryohei never ask Hibari to jiunge the boxing club despite Hibari's reputation and strength.
In Reborn! Colore, it is revealed that Hibari lives in an enormous mansion with decoration structures similar to the future Foundation base. Yamamoto says that he had heard rumors of Hibari's parents are from prominent families, as in families with an extremely famous history (often descendents from warlords). He also admits that he isn't sure if the rumors are true.