Charlotte Arrisaka Anderson is a 17-year-old of half-American, half-Japanese heritage. She possesses long blonde hair, typically braided and tied back, and striking emerald green eyes. Her standard outfit includes a white dress top, a maroon skirt, short white dress socks, black dress shoes, and a distinctive turquoise brooch necklace.

Originally an assassin, she was tasked with eliminating Siesta. After Siesta defeated her in combat, Charlotte developed profound admiration, abandoning her assassin role to idolize Siesta, whom she consistently addresses as "Ma'am."

Following Siesta's death, Charlotte became a subordinate to Fūbi Kase, aligning her within a law enforcement or investigative framework. She possesses notable combat skills; Siesta acknowledged her physical abilities while also stating they fell short of her own and explicitly assessed Charlotte as "not very smart" intellectually.

Her name reflects diverse origins: "Charlotte" (French, meaning "free man" or "petite"), "Arisaka" (Japanese, combining "Ari" 有 for "possess, exist, happen" and "saka" 坂 for "slope, hill"), and "Anderson" (patronymic meaning "Son of Ander/Andrew").