1girl aiming ankle_boots boots bullpup closed_mouth firing girls'_frontline gloves greyscale gun high_heel_boots high_heels highres jacket long_hair long_sleeves lying monochrome on_stomach one_eye_closed one_side_up pantyhose rifle shell_casing signature sniper_rifle solo tachibana_roku wa2000_(girls'_frontline) walther walther_wa_2000 weapon