I had never heard of the Ainu people before reading this. Obviously, that means any less accurate parts of their representation are beyond me, but so far everything I've fact checked looks great, and really adds to the realism. I've had Ainu music in the background while reading, and the vibes are off the charts. The tragedy inherent to a historical nature based story hits hard too, every narration about species that later became extinct, and cultural practices that were suppressed and became lost or near to as a result, adds to the story rather than taking us out of it. Usually I'm not a fan of obvious exposition, but here it's really working.