Kagerou is a character that appears in the Brave Police J-Decker series.
Kagerou was originally built as a prototype for Shadow Maru. They are similar in appearance, but he transforms into a draconic mode instead of a dog. Kagerou and Shadow Maru trained together, but he went rogue after finding that his memories were to be wiped when testing was complete. He evaded the Brave Police, who were assigned to capture him, and Shadow Maru allowed him to escape.
He was later captured by Ken Shinjo, who wanted to use Kagerou's Super AI to build a robotic version of himself since was in such ill health. Kagerou's body was turned into a mindless war machine, which Shadow Maru was forced to destroy in order to save the others.
Kagerou's AI was later installed in a submarine, which was sunk by the Brave Police after Kagerou refused to do as his captors demanded. His final wish was for Shadow Maru to join the Brave Police, which Shadow Maru honored.