Ritsuko Akagi is NERV's head scientist. The daughter of Naoko Akagi, the developer of the MAGI supercomputers, she is a lonely, cool and intelligent woman who has great affinity for cats and is completely devoted to her work. In flashbacks, it is revealed that she was one of Misato's first friends following the Second Impact. Ritsuko was also friendly with Kaji, and jokingly flirted with him, which is often misinterpreted by fans as evidence of a past romance. Additionally, she is a natural brunette who bleaches her hair. Along with Gendo and Fuyutsuki, she's the only person at NERV fully aware of the Evas' true nature and the purpose of the Instrumentality Project. Similarly to Gendo and unlike Misato, Ritsuko is willing to sacrifice the Eva pilots if the situation appears to warrant it. It is revealed in the later episodes that Ritsuko was romantically involved with Gendo Ikari. She feels betrayed by Gendo when she realizes that he was using her, mirroring her own mother's tragic fate. As revenge, she destroyed the Rei Dummy Plug system. She was shot dead at the end of The End of Evangelion, when she tried to launch the self-destruct to stop Gendo from initiating the Third Impact. She failed when Casper, the third MAGI computer which contained Naoko Akagi's personality as a woman, overrode the command. She was then shot and killed by Gendo.
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