Ruby is a brave and confident young girl. Others describe her as "little sisterly", as she is normally innocent and carefree, but can also be stubborn, childlike and ignorant to some more serious matters.
Ruby perseveres and is shown to be quite courageous and creative while in battle, often using her light weight and sniper blasts of the Crescent Rose to out-maneuver opponents. On her own, however, she is quite stealthy, and can often go into areas without being detected.
Ruby makes an appearance as a boss character in Rose Thorn. Documents reveal that she was infected by the mysterious plague while on a scavenging message. Ruby leads a group of infected consisting of various infected members of the Rose Warriors. Ruby is fought during chapter three.