Eiri High School

Eiri High School (鋭利学園高校) is a high school that is referenced in Shinyaku Toaru Majutsu no Index, during the last day of preparations for the Ichihanaransai. Little is known about the school, other than they are more brazen in their events for the festival compared to A Certain High School, which is close to it.

Ichihanaran Festival Arc
After Kamijou Touma comments that they cannot be too flashy with their displays in the Ichihanaransai as the teachers are going to be eying them, Aogami Pierce tells Touma that Eiri High School is having a beauty contest that included swimsuits. There is a rumor that their upperclassman, Kumokawa Seria is participating, as the school apparently allows outsiders to participate.

Later, the swimsuit contest is shown to be doing well. The competition has raised due to the fact that it allowed outsiders to compete. For example, queer swimsuits such as bandage ones appear during the competition, and especially, the rivalry between Kumokawa Seria and Shokuhou Misaki.