"I'd be in your side, Kagetora."
His real name is Nagahide Yasuda. He first appeared in Takaya's school, disguised as his classmate and best friend. Only Takaya was able to see through the ruse. Chiaki is stubborn and arrogant. He is the most frustrated with Takaya's memory loss. Though loyal to Kagetora he considers the man a rival as his magic is second strongest among the team.