The Headband girl (カチューシャ子 Kachūsha-ko?) is a recurring background character in Toaru Majutsu no Index. Originally only exclusively appearing in the novels, she later appears in both manga and anime adaptations of the series. She acts an easter egg in the series and generally appears in illustrations where Kamijou Touma's class from A Certain High School is involved alongside the Spiky-haired glasses girl who is apparently her friend, at least in the anime and manga adaptations.