Donbori Chiaki was a young anthropomorphic bear ronin.
Donbori Chiaki's father, Donbori Matsuo, had been a samurai in service to Lord Mifune, who died at the Battle of Adachigahara. To honour his memory, Chiaki undertook a warrior's pilgrimage to hone his skills. He was an honourable man, and his swordsmanship grew with experience. Little did Chiaki know that Matsuo had actually survived Adachigahara as a cripple, and was following him in secret, living vicariously through his pride for his son. When Chiaki was attacked by robbers, Matsuo saved his life, but had vanished by the time that Chiaki regained consciousness, leaving him to believe that his life had been saved by his father's old friend, Miyamoto Usagi.