Oku was the personal scribe of the Master of Water Asako Chukage at Twin Forks City, in 1198. Chukage had written a report intended for his fellow masters, where he explained there was some dark force at work in the Colonies, and that such a thing touched Chukage's mind. Chukage met Asako Jirou, who had to take the report back to the Empire. The Phoenix did not notice that Oku passed the Inquisitor a forgery, keeping the original papers for himself.