An unnamed student consistently designated "Girl with Glasses" engages in covert observation of the protagonist, frequently positioning herself out of sight behind corners or objects. She harbors a strong fascination with the protagonist's rarely heard voice, which she finds exceptionally cute. This motivates repeated attempts to startle the protagonist in hopes of provoking a vocal reaction, though these efforts invariably fail.

Her behavior includes possessive tendencies and interpreting other characters—notably the popular Ritsuki Yamamoto—as romantic rivals. This results in visible jealousy when rumors circulate about others having feelings for the protagonist. Despite her frequent stalking, other main characters remain unaware of her presence, rendering her effectively invisible to the group. This invisibility breaks only during specific instances like swimming lessons; without her glasses, she cannot see the protagonist clearly, incidentally preventing distraction, and her figure is noted as "good" in this state.

Physically characterized by purple hair and ochre eyes, she consistently wears glasses. Across all documented seasons, OVAs, and related media, she exhibits no significant character development, background story, or expanded role beyond these established patterns.