Nine

Nine is one of the main protagonists from Zankyou no Terror anime.

Nine is one of two members of a terrorist group known as Sphinx, working with Twelve as his primary partner. He and Twelve grow up together in an institution for children known as the Settlement. As adolescents, they engage in terrorist activities with unspecified motives at the beginning of the series, though their agenda becomes agonizingly clear by the finale.

Appearance
Nine is a tall young man of average build. His black hair has been cut short with bangs reaching his eye level. His eye color is inconsistent and often varies depending on the light or surroundings, in most cases usually grey or black. During most of the series, he is also seen wearing a pair of glasses with dark blue frames, which he loses near the end of the show. He is supposedly quite handsome, since several girls, as seen in episode 1, asked for his number.

He seems to favor dark colors, as he tends to wear dark clothing.

In his school uniform, which he is seen wearing on the cover and in episode 1, he wears black jeans with a brown belt and a white short-sleeved button-up with a green symbol on the right breast, presumably the school outfit for the men. In his street clothes, which he is seen wearing throughout most of the series, he wears a black, long-sleeved shirt with rolled up sleeves and gray jeans.

Personality
Nine is stern, aloof and stoic. He has a knack for devising ingenious criminal schemes while deftly covering up his tracks with his exceptional computing and hacking skills.

He was raised in a children's institution (little information is known about the facility) with Twelve, whom he was closest to, and Five. While escaping from what appears to be a fire that broke out at the institution, he underwent a traumatic experience of leaving Five behind as he was unable to save her. Ever since he has had recurring nightmares of the incident.

His emotional instability is exposed further when he is under great stress, as exemplified in episode 5 when he has a panic attack upon realizing that Five was onto him and his plans.

Twelve has described Nine as a sadistic but likewise a nice person. Despite being aloof, sadistic, blunt, and outwardly emotionless, Nine is nevertheless an extremely idealistic person who would go to great lengths to expose his history. He also believes in the value of human life, nearly sacrificing himself to save a sleeping girl on the train he and Twelve were supposed to bomb. In a strangely optimistic turn of fate, Nine also ultimately chooses not to detonate the final nuclear bomb, choosing instead to trust Shibazaki with their plan.

Trivia

 * The romaji for his name is "nain" in order to sound like the English pronunciation, "nine".
 * In his alias, Kokonoe Arata, is the kanji for 9.
 * He is capable of visualizing things as if they were right in front of him. An example would be when he is telling Lisa directions to place the bomb (even telling her the number of steps) in Episode 1. Another example is in Episode 6 and 7, he is able to visualize the chess board and where all the pieces were in order to figure out where Five hid the bomb.
 * He is seen to be less caring towards Lisa, unlike Twelve. However, this may be because he doesn't want her involved as he doesn't want her to be hurt.
 * As Sphinx Number 1, he wears a blue mask.
 * He has been seen to hate Five throughout the series, but at her death, he shouts out her name in surprise. It could be that because he couldn't save her back then, he felt powerless that he couldn't save her in the end.
 * His death was from the headaches caused by the experimentation. His death was symbolic as he was the brains of the operation.
 * His associated color from the Icelandic flag is blue.
 * The Icelandic music Nine is seen listening to throughout the series is the same music that's playing during the ending scene, in which Twelve and he die. We can tell this by listening to the music that is heard when Nine takes out his earbuds near the beginning of the first episode.
 * He has the same Japanese voice actor as Tobio Kageyama from Haikyuu!!, Kageyama's jersey number is Nine.
 * In the ending, Nine's cause of death was a side effect due to a drug related to the Athena Plan. This was a symbolism as Nine was the "Brains" of the Sphinx, as he knew his way around mathematics, technology and above more else; more clever than the average person.