There certainly isn't a shortage of peculiar girls in Yukari-sensei's homeroom class. Accompanying Chiyo are students like Tomo Takino, an energetic tomboy with more enthusiasm than brains; Koyomi Mizuhara, Tomo's best friend whose temper has a fuse shorter than Chiyo; and Sakaki, a tall, athletic beauty whose intimidating looks hide a gentle personality and a painful obsession with cats. In addition, transfer student Ayumu Kasuga, a girl with her head stuck in the clouds, fits right in with the rest of the girls—and she has a few interesting theories about Chiyo's pigtails!