Miyoko Kinjo is a student in the same class as Seishuu Handa and sits next to him. At first, she appears to be a kind and shy girl with a quiet admiration for Handa. Her nature changes drastically after a pivotal incident: Handa unknowingly helps her during a moment of deep despair, which she misinterprets as a romantic gesture. Convinced that Handa has fallen in love with her, she develops an obsessive and possessive personality. She adopts the nickname Eraser, a reference both to the eraser Handa lent her, which she now carries at all times, and to her self-appointed mission of erasing anyone she views as a threat to Handa. Despite her elegant and refined outward appearance, she harbors intense jealousy and a violent streak, and she will resort to intimidation and elaborate schemes to remove rivals. She perpetually misreads Handa’s social anxiety and avoidance as playful romantic tension, believing their relationship is fated. Handa himself remains completely unaware of her existence, which fuels her one‑sided devotion. Her primary conflict is with the Handa Force, whom she sees as interfering fanboys, and with any female student who dares to interact with Handa. Throughout the series, she does not undergo significant personal growth; instead, she remains a static parody of the yandere archetype, providing comedic horror through her over‑the‑top reactions and relentless pursuit. Her notable ability is the capacity to terrify even the most devoted members of Handa’s fan club, shifting from a poised schoolgirl to a menacing figure when her obsession is triggered. Her role in the story is that of a comedic antagonist, illustrating the absurd lengths of one‑sided infatuation and contributing to the series’ humor through exaggerated misunderstandings.