A rogue scientist from a pharmaceutical company who used military research originally conducted by Nijū Mensō to create supersoldiers akin to "Human Tanks". She and her partner, Takashi Tsuya, experimented on themselves and enhanced their bodies, but when they found they could not reach the intended results of the research, they sought to find a cure by approaching Chiko, believing that the legacy Nijū Mensō left to her would be the research they needed. Dr. Tsuya dies when his body loses control from the experiments while Dr. Kayama escapes, leaving Chiko a warning that she will be approached by many people seeking the legacy of Nijū Mensō. Dr. Kayama continues to search for a cure for her condition, eventually saving Ken from Kakihara's agents, recognizing that they are more advanced products of research by Seiji Tamiya to create human tanks, and works with Ken to defeat them.

(Source: Wikipedia)