Akari is a character from the manga and anime series Karneval. He is a doctor and a distinguished researcher working for the government, serving as a vital member of the Research Tower, which is referred to as the Tower of Research. His status is so significant that he is considered a national SSS-level important person. Physically, Akari is an adult male with pink hair that falls to his neck and pink or peach-colored eyes. He stands approximately 185 centimeters tall and his birthday is on December 23.

In terms of personality, Akari is described as having a dominant and straightforward nature. He can be blunt and insensitive at times, with a habit of stating the truth directly and suggesting that those who dislike a situation should work to improve it. Despite his cold or harsh exterior, he is a good person who is genuinely liked by children and small animals. He has high self-esteem and takes great pride in his work as a researcher, in which he is exceptionally capable. His straightforwardness often puts him at odds with the nurses, though there is also a faction among them that wishes to support him. Akari has a strong dislike for people who use clever words to appeal to others. He also harbors a specific and strong dislike for his colleague Hirato, who enjoys teasing him, though he has other, completely different reasons for disliking him as well. He considers both Hirato and another colleague, Tsukitachi, to be more annoying than friendly. Akari enjoys his research, exploring undeveloped areas, and playing board games. His preferred foods include black tea and brown sugar from corals.

Akari’s role in the story is primarily tied to the inner workings of Circus, the organization that serves as the series' central authority. He is in charge of analyzing information and conducting research, particularly regarding the enigmatic organization Kafka and the mysterious figure of Karoku. For instance, he has been tasked with decrypting and analyzing partially burnt research notes to uncover clues about Kafka's activities. His expertise allows him to identify that the level of skill in the notes likely came from a mind trained at a Circus facility. He also deals with internal matters, such as investigating potential information leaks from within his own department and requesting classified information about a past "Schism" within the organization.

Key relationships define much of his interaction with the main cast. He has a significant connection with Hirato, a field agent from the same organization. Though they are old acquaintances, their relationship is strained and characterized by mutual annoyance, with Hirato often taking pleasure in teasing Akari. Akari also serves as a mentor to a younger character named Azana, having taken on this role after Azana lost his family. He is also an old acquaintance of a character named朔 (Saku), and was a teacher to both Saku and Hirato during their time at a government academy. His development is shown through his persistent efforts to solve the series' central mysteries from a scientific and analytical standpoint, dealing with the frustrations of bureaucracy and information control within Circus while mentoring younger members. His notable abilities lie not in physical combat, but in his exceptional intelligence and expertise as a medical doctor and scientific researcher, making him an indispensable asset to the government's operations.