Rimi is shown as a cheerful and kind girl, acting as a friend and support for Taku. Rimi’s original personality no longer exists, and her current personality is one that was born from a delusion she had when being tortured. She is kind and caring towards Takumi Nishijou and others, although the Takumi she really cares about a whole lot is not the borderline-
hikikomori one who calls himself
Neidhardt online, but the prematurely aging patient at
AH Tokyo General Hospital who calls himself
Shogun online.
She pretends to be dumb and not understand things, but she actually understands everything and keeps it secret. She also pretends to be cheerful, but that is also just a front and really, she is suffering quite a bit and has low self-esteem, and is not quite as kind and caring as she pretends to be. One of her main motivations is to prevent the Neidhardt version of Takumi from awakening, because she wants to protect Shogun and is obsessively devoted to him. Her
gigalomaniac powers give her the abilities of mind-reading and mind control, although her mind control only works on normal people, not fellow gigalomaniacs like Takumi. Her mind-reading is more powerful and works on everyone, including fellow gigalomaniacs.
She uses her mind control abilities to become a student at Suimei Academy and friend of Takumi and Misumi, and to convince everyone besides her fellow gigalomaniacs that she has been a student there and friends with them a long time. Since Takumi is immune to her mind control, she needs to take a more direct approach with him and persuade him through both conversation and her actions, as well as by manipulating others like Daisuke Misumi through mind control. She also constantly uses her psychic mind-reading powers during conversation, sometimes accidentally replying to things the other person was thinking but not saying out loud, but thankfully for her, nobody figures this out.
So despite the warm, caring, somewhat ditzy personality she pretends to have, deep down inside she is actually fairly cold, calculating, and manipulative, in order to achieve her own goals. This is typical for gigalomaniacs, who have similar personalities to megalomaniacs and who all tend to be manipulative, obsessive, self-centered, and delusional, with an unstable sense of self. In fact, all of the main characters in
ChäoS;HEAd, with the exception of the fictional
Seira Orgel, are gigalomaniacs who have those same personality traits of narcissism.
However, Rimi claims to be Taku’s genuine friend and that she has always cared for him. She also has a habit of saying “Bishi!” (ビシィッ！,
Bishī!), making it her catchphrase (translated as “Ten-hut!” or “Salute!”, which she says while saluting). “Bishi!” is a made-up catchphrase just like “Tutturu~!” and “El Psy Kongroo” are in
Steins;Gate, and like those other phrases, it doesn’t actually mean anything. She usually says it when Taku is feeling bad, to try to cheer him up, and always salutes when saying it. Her favorite food is buckwheat, and she is the main heroine of
ChäoS;HEAd.
And Rimi uses her psychic powers for good, like after
Ayase Kishimoto attempts suicide and Taku
real-boots a flowerbed for her to land on on October 27, 2009, and Ayase is taken to the hospital, Rimi uses her mind control powers on the doctors, nurses, and medics to make sure Ayase is given top-priority treatment, higher priority than all the victims of the
Second Melt earthquake that happened the same day, who are mostly just unconscious and don’t require immediate care like Ayase.
. Then I finally win!