A girl from Ishida and Nishimiya's elementary school and the girl that Ishida was closest to at school. Ishida remembers her bossing him about and also being his main helper in bullying Nishimiya. After having separated from him since middle school graduation, Ueno runs into Ishida years later, herself now working in a cat café.
It is revealed that Ueno is in love with Ishida and originally picked on Nishimiya to impress him, however when she learned that Nishimiya was cleaning the offensive words off Ishida's desk before he could see them she convinced herself that Nishimiya also loved Ishida and was using her disability to get his attention, leading her to grow jealous and resentful toward Nishimiya. However, unlike Ishida, Ueno never learns her lesson and continues to hate and bully Nishimiya once she reconnects with her through Kawai and Sahara (whom she remained friends with). Ueno watched Ishida suffer through middle school—still being bullied for what he did to Nishimiya—and feels bad herself for being unable to do anything. She claims that their sadness, from her having to cut off contact with Ishida to him hating everyone, including her, has all been because of Nishimiya. In truth, however, Ueno is irritated because Nishimiya never defends herself whenever she is bullied, thinking her as a weak person because of this. Despite being within the group of friends, Ishida still imagines Ueno with an X over her face, showing his disgust with her, until after his release from hospital, after which Ueno is dragged by Sahara to become her assistant as a model.