I dunno sirs, on one hand being committed to the sfw nature of the place is commendable, the fox does look suspiciously child-like, the author does draw them in an odd way that can probably provoke the "uoooh ToT" types. That, and also making 3 threads with the fox in question in a row does seem odd.
But on the other hand the comic itself doesn't cross the line (at least it didn't by the time I'd dropped it, which wasn't that far in), the kitsune herself is like 900 years old (because of course she is lmao).
Thus it's understandable how this could be a dilemma. Moderate the provocateur or those who take the bait? I'd aim to base the judgement on experience and precedent. The core userbase of the place cannot be that big and there shouldn't be that many trolls around. Is this a known troublemaker? Basic janitor tools are probably limited but those with full access can probably see the whole shebang down to the gpu model in case of some browsers (*cough*brave*cough*), so they can profile for users to pay attention to and hand down the bulletins. Malicious intent → moderate thread; no sign of malicious intent but questionable taste/quality → moderate responses. Presumption of innocence.
If the case isn't cut&dry there ought to be time to reach consensus on things like these before acting. Maybe something good will come from this incident as it gets added to the list of examples to build a list of precedents and examples of moderation, whatever the final verdict may be.
Ideally there'd be internal moderation guidelines for borderline cases (even if they are not publicly shared on the rules page), just so that the team is more in sync.
Last idea: the "built like a kid, acts like a kid but isn't a kid or mortal" trope isn't new or original. Surely some other sfw places (be them altchans, forums, boorus or anything of the sort) have run into a similar dilemma; how do they treat it? Can't come up with any examples atm sadly, nothing comes to mind.