True indeed, but just imagining such existences and comparing them to the real counterparts (animals), it seems to me a fox, which can be tamed to a certain extent (and after generations of selective breeding would become 100% domesticated), would be more malleable than a spider. Of course there actually aren't spiders in RL with developed enough brains that one could judge what kind of tendencies and personalities they might have if truly intelligent. But even so, something of the original does remain even in this series. It's just my opinion, but I do feel like Yotsuyu simply won't be as human as Kogane, ever, on a very basic level. A good detail, if I am correct.