Kashiwagi Haruko sports blue hair styled in a bob cut with spiky bangs, green eyes, and a slim, pale frame. Born October 10, she initially appears as a popular, athletic high school student, serving as a lacrosse goalkeeper and former basketball club member. Her cheerful, easygoing nature endears her to peers, though she playfully teases her two younger brothers, whom she financially supports.

Transitioning to a military role, she becomes a 2nd Lieutenant in Special Task Force A-01 under the callsign Valkyrie-6. Specializing in tactical analysis and combat leadership, she trains Squad 207A alongside Suzumiya Akane. While mentoring, she adopts a blunt, pragmatic communication style, balancing this with a nurturing demeanor as she shares family stories and assumes an older-sister role for comrades.

Her operational history includes the Sadogashima recapture mission, where her tactical surface fighter suffers critical damage from Grappler-class BETA before her fatal encounter with a Fort-class BETA’s dissolving liquid. Media depictions diverge: the original visual novel and manga show instantaneous dissolution, while the anime portrays a prolonged cockpit breach and organ dissolution with flatlining vitals.

Expanded narratives explore romantic subplots where she openly competes for affection, while a spin-off delves into her younger brother Taichi’s perspective, expanding her familial context. Supplementary trivia notes her fondness for Chinese rice bowls and romantic engagements predating central events.