The current kbin domain block doesn’t really work well as an instance block. What it does is block any post linking to that specific domain. It will block a nsfwlemmy user posting images to their own instance, but it won’t block lemmy.world or lemmy.ml user posts there as they link to their own respective domains instead. It also won’t block any post from that instance linking to a 3rd party domain either.
FYI the episode discussions on anime@lemmy.ml are automated by a bot (the same used on Reddit in fact) and us Kbin users can’t see bot posts, so it looks like there are none. I have high hopes that the next big Kbin update remedies this issue.