An 18-year old honors student. She has both the brains and beauty and is said to be a dream girl of many young men, making her popular in school. Up until the last two days of the game, Io is constantly apologising and always compromises, agrees with others and never forces her own viewpoint on others out of fear of being hated. This frustrates Airi several times because she thinks that Io is very superficial, and when she tells Io to say what’s on her mind, Io realises that she hardly even has any opinions of her own. She pauses a lot when talking and Yamato chews her on her non-confrontational policy. At the last two days, she eventually found her resolve and decided to be more courageous on expressing her own feelings. She seems to develop a crush on the protagonist.