Etsuko Takayanagi is a celebrated high school student, excelling academically and athletically through her tennis prowess, while embodying an idealized image of purity that earns her the title “Eternal Virgin.” This mystique fuels widespread admiration and obsession, notably from the protagonist, who covertly obtains illicit photos of her vulnerable moments, such as wardrobe malfunctions during sports.

Her carefully constructed persona unravels as hidden truths surface: she secretly bargains with a teacher for academic favors, exposing a stark contrast between her virtuous facade and private transgressions. Supernatural forces amplify this duality, publicly exposing her secrets and provoking a violent confrontation in a remote area. There, a supernatural influence triggers a visceral transformation, morphing her demeanor into one of unbridled aggression and homicidal fury directed at the protagonist.

As student council president, Etsuko retains her position as the school’s most revered figure. A fateful meeting in a public space escalates to a clandestine encounter within an abandoned facility, where her poised, worldly behavior clashes with her virginal reputation. Chaos erupts when external interference disrupts airborne machinery nearby, resulting in an unintended fatal accident.

Though her story concludes with death across adaptations, supernatural hints suggest potential resurrection. Her arc dissects the fragility of perception, weaving deception and idealized imagery into consequences that propel the protagonist into profound moral and existential turmoil.