Chitose Kaginoji is a 14-year-old girl with bright amber eyes and blonde hair accentuated by a vibrant red ribbon, her attire often blending elegance and flair through pieces like a crimson dress layered over a black skirt. Her tsundere personality flickers between sharp assertiveness and tender vulnerability, prone to whining or blushing when flustered. She harbors an almost naïve gullibility, readily accepting even the most absurd statements from Tsukasa Yuzaki, whom she reverently calls "Nee-sama" despite sharing no familial ties.

This devotion traces to a childhood incident where Tsukasa rescued her from a cliff’s edge, igniting Chitose’s lifelong pledge to repay the debt. Her loyalty fuels relentless opposition to Tsukasa’s marriage to Nasa Yuzaki, whom she deems unworthy. Enlisting her maids, Aurora and Charlotte, she devises schemes to sabotage the union—luring Nasa to her villa to stage a scandal or infiltrating the couple’s honeymoon to stoke discord. Yet beneath her antagonism lies a fierce protectiveness, likening Tsukasa to a fragile "glasswing butterfly" requiring meticulous guardianship.

Chitose’s heritage includes being the granddaughter of Tokiko Tsukuyomi and daughter of Shiori, a famed Japanese-style painter. Rumors hint at a quarter-American lineage via her grandfather, though unverified. Privilege defines her life, marked by limousines, a private villa, and reliance on maids for daily tasks—though Charlotte’s eccentricities frequently derail her strategies.

Her interactions with Nasa gradually erode her disdain. A candid Kyoto exchange exposes his sincerity and methodical nature, prompting reluctant respect. While still irked by his ignorance of Tsukasa’s past, she ceases active interference in their marriage. Academically adept and popular among classmates—particularly girls—she occasionally skips school to prioritize Tsukasa-centric pursuits.