It couldn't get Yamamoto Tsunetomo (Hagakure, which is basically THE treatise on how to be a samurai). I'm not at all surprised that it's got such a sizable library of Japanese characters, though.
EDIT:
For Archer of Fate/Stay Night, after several questions
Akinator: Does he have white hair?
Me: ....
Akinator: Does he wear a red suit?
Me: Well, that was quick. GG, Akinator.
Akinator: Is he someone's servant?
Me: *facepalm* It knows too much! Stop rubbing it in!