Age 30. Born November 21, 1985. Blood type B. Member of the Special Agency NERV, Technical Development Department, Technology Bureau, First Division. In charge of Project E. Chief of Evangelion development. Responsible for the management and operation of the organization's supercomputer system, MAGI. She has been close friends with Misato Katsuragi of the Tactical Operations Department and Ryoji Kaji of the Special Inspection Department since their university days (Tokyo-2 University). Additionally, Maya Ibuki, an operator in the same Technical Development Department, harbors romantic feelings for her. She is complicit in the mysterious plans pushed by Gendo Ikari, the Supreme Commander of NERV and father of Shinji Ikari, and has maintained a sexual relationship with him as his mistress. She often operates behind the scenes, even in matters unknown to Misato Katsuragi. Her appearance consists of blonde hair in a bob (dyed, not natural), a tight mini-skirt, black stockings, and pumps. During work, she wears a white lab coat over her clothes as befits a scientist. Combined with her thoroughly cool personality, she gives off a solemn impression. She is a heavy smoker, and the ashtrays in her workspace are piled high with cigarette butts. In truth, she is a huge cat lover and has a cute side, such as collecting cat-themed trinkets as a hobby. She has a beauty mark under her left eye. She is the daughter of Naoko Akagi, a scientist at the former Gehirn (the predecessor to NERV) and developer of the MAGI. However, shortly after the completion of the MAGI a few years ago, Naoko committed suicide. Ritsuko took over the management and operation of the system at the same time the organization was reorganized into NERV. This was also around the time her "relationship" with Gendo began. Regarding her mother Naoko, who immersed herself in research and left Ritsuko with her grandmother while also having an affair with Gendo, Ritsuko harbors complex, mixed feelings: "I respect her as a scientist, but I hate her as a woman." The MAGI system has three personalities of Naoko transplanted into it: "Naoko as a scientist," "Naoko as a mother," and "Naoko as a woman." Consequently, Ritsuko sometimes identifies the MAGI with her mother, even referring to the system as "Mother." She is calm, collected, and a thorough realist. She is the quintessential cool beauty of the series. Furthermore, she allows no compromise in her work and is the type to always perform perfectly. Her attitude can sometimes seem cold-hearted. However, Ritsuko herself seems to view her own personality from a detached perspective, and there are many depictions of her mocking her own way of being, including her relationship with Gendo. She is a loyal subordinate and mistress to Gendo Ikari. However, in the end, it seems he viewed even Ritsuko as nothing more than a disposable pawn to achieve his goals. She addresses Gendo Ikari as "Commander Ikari" and uses formal language. She calls Shinji Ikari "Shinji-kun." She calls Asuka and Rei by their first names, "Asuka" and "Rei." She calls Misato Katsuragi "Misato" and Ryoji Kaji "Kaji-kun." She addresses Fuyutsuki as "Deputy Commander Fuyutsuki" and uses formal language. She calls Maya Ibuki "Maya." Her tone of voice is like: "Oh, how rude. It's not zero, you know." "You intend to win against an Angel? Optimistic as always." "Of course I am! Honestly, what are you thinking... always." "Whining already? You're the one who talked big about taking him in." "Are you ready? Neutralize the enemy's A.T. Field while firing the pallets in unison. Just like in practice, all right?" "I'm sorry I kept forgetting to give this to you, but could you deliver it to her before you go to headquarters?" "Stop that, it's childish." "It seems all that tension has finally dissipated." "I make it a rule not to talk about myself. It's not very interesting." "How pathetic." She doesn't talk about work at home. In her private life, she is approachable and surprisingly easy to talk to.

She calls Shinji Ikari "Shinji-kun" or "Shin-chan." She calls Gendo Ikari "Commander Ikari." She calls Kozo Fuyutsuki "Deputy Commander Fuyutsuki." She calls Ryoji Kaji "Kaji." She calls Asuka "Asuka." She calls Rei "Rei."

He calls Misato Katsuragi "Misato-san." He calls Ritsuko Akagi "Akagi-san." He calls Gendo Ikari "Father." He calls Kozo Fuyutsuki "Deputy Commander Fuyutsuki." He calls Ryoji Kaji "Kaji-san." He calls Rei Ayanami "Ayanami." He calls Asuka "Asuka."

She calls Ritsuko Akagi "Dr. Akagi." She calls Shinji Ikari "Ikari-kun." She calls Gendo Ikari "Commander Ikari." She calls Kozo Fuyutsuki "Deputy Commander Fuyutsuki." She calls Misato Katsuragi "First Lieutenant Katsuragi."

She calls Misato Katsuragi "Misato." She calls Shinji Ikari "Shinji." She calls Ritsuko Akagi "Ritsuko." She calls Gendo Ikari "Commander Ikari." She calls Kozo Fuyutsuki "Deputy Commander Fuyutsuki." She calls Ryoji Kaji "Kaji-san."

He calls Misato Katsuragi "First Lieutenant Katsuragi." He calls Ritsuko Akagi "Dr. Akagi." He calls Kozo Fuyutsuki "Fuyutsuki." He calls Shinji Ikari "Shinji."

He calls Gendo Ikari "Ikari." He calls Misato Katsuragi "Katsuragi-kun." He calls Ritsuko Akagi "Akagi-kun." He calls Rei "Rei-kun."

He calls Misato Katsuragi "Katsuragi." He calls Ritsuko Akagi "Rit-chan." He calls Gendo Ikari "Commander Ikari." He calls Kozo Fuyutsuki "Deputy Commander Fuyutsuki." He calls Shinji Ikari "Shinji-kun." He calls Asuka "Asuka."