Waka Kisaki, a first-year student at Aokisora High School, lives next door to Mikado Nakajima—her childhood friend and the school’s student council president. Her given name, blending the characters for "harmony, peace" and "rack, erect, frame," contrasts her surname’s meaning of "tree" and "cape." Outwardly poised and elegant, she harbors a spirited, tomboyish nature and a naïve charm, traits she often veils around Mikado, whom she views with sibling-like admiration and dependence. Despite her effortless academic excellence, her interactions with Mikado remain tinged with unspoken tension, as he quietly harbors unrequited romantic feelings for her.

When classmates urge her to campaign in student council elections during the cultural festival, her role within school affairs begins to expand, paralleling Mikado’s presidency. Their shared history as step-siblings weaves a dynamic of mutual reliance and unresolved emotions, shaped by her habit of softening her true demeanor in his presence and his enduring, unreciprocated affection.