Does Japanese even have a grammatical equivalent to that? The translator might be to blame, here.
There are honorifics in Japanese (Keigo), which can help stress a grammar-equivalent meaning. But Remilia is not usually as polite or honorific with Sakuya as you might think. Calling her 「あんた」 for example is a very... Informal and at times rude way to call someone, but happens when you're either upset or just don't like someone. That's why I really don't think honorifics really fit this situation due to the informal nature of the conversation they're having. If anything, Remilia is being very demanding of Sakuya instead.
There are honorifics in Japanese (Keigo), which can help stress a grammar-equivalent meaning. But Remilia is not usually as polite or honorific with Sakuya as you might think. Calling her 「あんた」 for example is a very... Informal and at times rude way to call someone, but happens when you're either upset or just don't like someone. That's why I really don't think honorifics really fit this situation due to the informal nature of the conversation they're having. If anything, Remilia is being very demanding of Sakuya instead.
I'm not sure that actually answers my question. I was asking if there's an equivalent to "whom vs who" in Japanese. I'm not sure what Remilia being informal with Sakuya has to do with proper grammar. And of course she's demanding of Sakuya, Sakuya is her maid.
I'm not sure what Remilia being informal with Sakuya has to do with proper grammar.
In my experience, no one ever uses "whom" in a real conversation unless it's in an extremely formal context (or they're an armchair linguist with an axe to grind). Outside of people banging pots about it being "proper" grammar on the internet, the only time I've ever seen or heard the word "whom" being used was in the Bible (It's in a very similar boat to "thee" or "thou", in that regard).
Not saying it doesn't fit Remilia, given her age, but in my experience "whom" in the modern day is very much dependent on how formal/informal the dialogue is.
(It's in a very similar boat to "thee" or "thou", in that regard).
Sort of the opposite way around, though. Thee and thou are remnants of the fact that English used to have both formal and informal second persons (as a lot of languages, e.g., French, Spanish, and German, still do), but they were the informal forms. Over the past couple of centuries, English has evolved to use what used to be the formal/respectful versions of second-person address at practically all times, even among intimates (even as the rest of the language has become progressively less formal), but there was a strong distinction not all that long ago. Quakers used to get into trouble for addressing everyone as "thou" regardless of context not because they were being archaic, but because they were being insultingly familiar.
