AppearanceFace & Hair: Sharp, deep sapphire-to-dark-blue eyes, thin eyebrows, and unruly, medium-length black hair tied into a low, messy ponytail.Expression: Almost always wears a serious, unbothered, or stern look on his face.Uniform & Haori: Wears a dark cyan-tinted standard Demon Slayer uniform paired with an iconic, split-pattern haori.Mismatched Haori: One half is solid red (from his late sister Tsutako) and the other half is geometrically patterned with green, orange, and yellow (from his late friend Sabito).PersonalityStoic & Quiet: Appears aloof, emotionless, and distant to others, often coming across as socially awkward or unfriendly.Strong Sense of Justice: Fiercely intolerant of those who throw away their lives or do not know their own limitations, showing absolute zero mercy toward demons (with the sole exception of Nezuko).Survivor's Guilt: Harbods a deep inferiority complex believing he is unworthy of being the Water Hashira because he survived past tragedies through the sacrifices of his sister and best friend Sabito.

Physical AppearanceBuild: Short and petite with a frail frame that makes people underestimate her physical strength.Eyes: Large, gradient purple compound-like eyes with no visible pupils.Hair: Wavy, shoulder-length hair fading from black to dark purple, styled in a bun and pinned with a white-and-purple butterfly ornament.Attire: Standard dark purple Demon Slayer uniform paired with a distinct, inherited butterfly-wing patterned haori that fades from white to turquoise and pink.Personality TraitsThe Cheerful Façade: She constantly wears an easygoing smile and acts bright and friendly around others.Hidden Vengeance: Beneath her calm exterior lies intense rage and sorrow over losing her family and older sister, Kanae, to demons.Sadistic Teasing: She enjoys playfully provoking and teasing other characters, especially Giyu Tomioka.Brilliant Intellect: Highly cunning and medically gifted, she uses her brain and unique wisteria poisons to make up for her lack of muscle strength.