Responses
I don't see it as a spoiler. The manga heavily implied that was the case before the anime confirmed it.
True, but it's mostly for the few who didn't think too much about it. It's always good to warn people of spoilers even if some already suspected something because there's bound to be someone who will/would get upset by having that spoiled for them..
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So the anime revealed that there is in fact something in Ashiya's line, that it's surprising that a human has that name... Tbh, I would have preferred that the anime didn't spoil that if it is true and left it as a cliffhanger instead... Hopefully we'll find out more about it on the manga.