Kaere Kimura is a student in class 2-He who recently returned to Japan after living abroad for only three months, contradicting her returnee status; her exact country of origin remains unspecified despite initial suggestions of American ties. This brief experience abroad sparked dissociative identity disorder due to conflicting cultural expectations.

She possesses long blonde hair and wears a modified school uniform: a suit, tie, and short skirt, distinguishing her from classmates. Her disorder manifests through two primary personalities: "Kaede," a gentle, traditionally Japanese yamato nadeshiko persona well-versed in local culture, and "Kaere," a foreign-influenced personality critical of Japanese customs who frequently threatens lawsuits. The Kaere persona dominates more often.

Her given name acts as a trigger for personality switching, deriving from the imperative form of "kaeru" (to return/go back). The Kaere personality frequently references bizarre customs from her supposed home country while expressing disgust toward Japanese traditions. She exhibits left-handedness, observable in artwork.

A recurring trait involves frequent panty shots, often featuring unusual patterns on her underwear. Deeper exploration reveals she previously possessed a third personality that balanced the Kaede and Kaere extremes; this identity fragmented after a psychotic breakdown triggered by classroom interactions. Further developments indicate additional split personalities emerge later, each representing different countries.

The friction between her Japanese heritage and foreign experiences remains central to her psychological instability, with her identities embodying opposing attitudes toward cultural assimilation.