Kaori Misaka
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Kaori Misaka
Kaori is mainly in Shiori's story, but is regularly seen due to her being Nayuki's best friend and Yuichi's and Nayuki's classmate, as well as the class representative. She is very smart and knows a lot about the schoolmates and townspeople, but doesn't appear to be aware of any of the supernatural things that happen, even after Yuichi's caring saves someone close to her. Her surname and appearance indicate that she is Shiori's sister, and Shiori affirms this, but Kaori vehemently denies it. Jun Kitagawa once commented how she started to act differently once they entered their second year in high school.
Kaori's main involvement in the story is during her younger sister Shiori's arc. When Yuichi starts to spend more time with Shiori away from school, Kaori asks Yuichi to meet one late night at school to tell him something. At their meeting, Kaori informs Yuichi that Shiori does not have very long left to live, and that by her next birthday, Shiori may die. Kaori tells him that the reason she does not want to get close with Shiori is that she does not want to feel the intense pain that will result from Shiori's death. Kaori breaks down after saying this, crying on Yuichi and lamenting the pointlessness of Shiori's birth.
After this point, Kaori starts to avoid Shiori even more than usual. When confronted by Yuichi about how she has been acting, Kaori tells him that she has no younger sister. For Shiori's birthday, Yuichi decides to throw a birthday party at a local café with several people invited including Ayu Tsukimiya, Nayuki Minase, Jun Kitagawa, and even Kaori herself among others. At the beginning of the party, Kaori is not there, though shows up later. The mood at the party instantly grows cold when Kaori arrives, as she still refuses to acknowledge her sister's existence despite the situation. After the party, however, Kaori finally accepts Shiori as her younger sister and as she is walking away to leave Yuichi and Shiori alone for the rest of the day, she tells Shiori that they should talk later to catch up on things. This rightfully so makes Shiori very happy, and she thanks Yuichi for all he has done. She manages to stay by Shiori's side after this even though the chances of her recovering are very slim. In the end, when Shiori does not die, Kaori does not change and continues to stay by her sister's side
