Futaba, Rio

双葉理央

Rio Futaba (Futaba Rio) is a main character in the Seishun Buta Yarou wa Bunny Girl Senpai no Yume wo Minai series and a second-year student at Minegahara High School. She shared a class with Sakuta and Yuuma during their first year and is the only member of the Science Club.
She is a stoic and blunt girl with substantial knowledge of science, including chemistry and quantum physics. She has a sharp sense of humor and is even more sarcastic and straightforward than Sakuta. Despite her stoic nature, Rio displays various emotions, such as love, holding affection for Yuuma, as well as anxiety. She is also genuinely kind and loves her friends.
Rio is implied to have experienced neglect. Additionally, she has no siblings, which further suggests that she chooses to be alone because it is her comfort zone, one she unwillingly developed due to her lonely childhood. However, this loneliness gave her the courage to approach Sakuta first when they were in the same class, as she saw him as an outcast just like her.
Before experiencing it herself, she was unwilling to believe in the existence of Adolescence Syndrome, but she did acknowledge the abnormal phenomena it induces and connects them with various scientific theories and principles.
At some point, Rio's feminine body parts developed much earlier than those of her classmates. Once she noticed how some boys were ogling her, she began to hate her body and felt like "a truly filthy being."
At some point during her time in the science club, she became known for performing experiments that caused power outages and small fires.

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