Shiro Kazami was a biochemistry student who witnessed a murder committed by an agent of Destron. He rescued a potential victim and took her in at his home until his family was killed to eliminate witnesses. Despite this tragedy, he vowed revenge against Destron and asked the Riders to transform him into a cyborg, which they refused. When the Riders were captured during their mission, Kazami set out to save them but ultimately succumbed to his injuries in battle. As a result of his sacrifice, the Riders decided to alter him into Kamen Rider V3.