Seriously... nobody commenting on this post-mortem. The fact that Rei and Soya are basically on the same wavelength... I find that revelation to be quite fascinating. Even for someone totally lost with Shogi, like myself, I can tell the writing is saying something really significant here about how they're both wired so similarly... Rei may not be able to read him, really (at least not yet), but Soya understands him. Probably in a way he just hasn't understood anyone else.
I dunno, maybe I'm just talking out my ass... But still, it feels important, those moments.
Also the revelation that Soya can't exactly hear. (or, rather... he has intermittent hearing loss. The Chairman's going to explain it next chapter or so, I think)
Such a genius, but he's basically made so helpless by one of his senses vanishing on him randomly.