Isamu Fuwa

Isamu Fuwa is the squad captain of A.I.M.S. and the secondary Rider of Kamen Rider Zero-One. He has the power to transform into Kamen Rider Vulcan.

Past
When Isamu was young, he bore witness to the Daybreak Town incident, in which thousands of HumaGears were hacked by MetsubouJinrai.NET and made to go rogue and rampage, eventually destroying the entirety of Daybreak Town. Isamu was one of the few survivors of the incident and the event, along with its coverup by Hiden Intelligence, led to Isamu developing a distrust of HumaGears.

In A.I.M.S.
Isamu's hatred of HumaGears eventually led him to join the Artificial Intelligence Military Service (A.I.M.S.), an agency designed to investigate and combat rogue HumaGears, where he eventually rose to become captain.

After MetsubouJinrai.NET reemerged and began hacking HumaGears to turn them into Magia, Fuwa led an A.I.M.S. squad in response to the attacks. Isamu eventually broke into A.I.M.S. armory and took the Shot Riser along with the Shooting Wolf Key, allowing him to transform into Kamen Rider Vulcan.