Answers also behind a cut (also, not all of the answers will come at once, some I need to read up on more and some will be answered when I do that summary/partial translation of the two unscanlated chapters):
A: I don’t think so. Louise says something odd in katakana, but “moon slavery” doesn’t quite fit. “Moon slave berry” would fit the katakana, but that’s probably not what she’s going for either. It sort of sounds a vaguely British made-up name ending in “-berry” or “-bury”.
B: It’s metaphorical. In the sense that once a seed sprouts and spreads roots, it’s stuck in the ground. Similarly, the girls of Jiaiin are also “rooted” there and will be cultivated... or weeded out.
C: No idea. Most likely just generic supernatural shenanigans. It’s possible that something not human decided to have private time with Tituba after Chloe left the room, since I’m not so sure that Tituba is just a maid like the others.
D: This will be addressed in the final two chapters.
E: This seems like a mistranslation. In the original Japanese, Makina was saying that there are students who actually graduate, so it would be safest to go along with Chloe and her cult of fanatical maids.
F: Yes, there seem to be some maids that aren’t entirely in on Chloe’s insanity and genuinely care about the students. I notices a somewhat plump, short-haired maid who can be seen alongside Elizabeth at times in early who might also fall into this category (though she doesn’t seem to show up later).
G: I need to read up on this.
H: I think it’s just the one ghost haunting the dormitory.
I: According to Makina’s explanation, the reapers are the manifestation of malice that gathers in the forest. In the original Japanese, they are still called reapers, but it’s spelled with the kanji for “presence”. Basically, I think they’re just monsters produced by the general fucked-uppedness of the town.
J: No. I think the affair with Imawa and Chikako was supposed to be an entire character arc for Louise that wound up getting scrapped due to the manga be forced to end early (the end feels kind of rushed, so this is what I think happened).
K: I need to read up on this more, but it sounds like it might be an issue with the translation.
L: You’re correct in that “Nahato” is the Japanese transliteration of “Nacht”. If you do a google search of both words together, you’ll find several examples of other characters named Nacht in Japanese media. His motivations are partially revealed in the last two chapters. I still don’t know what he was trying to accomplish with the recording device.
M: Also something partially addressed in the last two chapters.
N: The contents of the box are revealed in the last chapter. No-face’s true identity is not.
O: I don’t believe so. I might follow up if I find anything out.
P: I think Elizabeth and Betty are sisters. And that is Elizabeth in the page 11&12 spread, but I don’t think that’s her on page 14. It will be cleared up a bit when I post about chapter 23.
Q: This is a mistranslation. The actual line states the Chloe would be the one to take care of the mysterious man’s “child”. In other words, the box.
R: I have no idea about this. In chapter 23 she’s addressed once as “Chloe Andrew Canon” (no guarantees about correct spelling there). So she seems to take a lot of different last names.
S: I would need to look at the scanlation to confirm this, but in the Japanese the driver is only referred to as “Untensha-san” (literally just “driver”).
T: It could be that the townspeople aren’t truly human (I especially have doubts about that hulking shadow that was standing behind Makina). But most likely that was just artistic effect to illustrate the madness of the situation and the breakdown of what little facade of normalcy had been left intact up until that point.
U: A lot of this is addressed to some extent in the last two chapters. I will say one thing now, though. Chloe needed virgin sacrifices for the box and her blood baths. “Good” girls were significantly less likely to get killed through the Dolls Fall game and used as sacrifices. So it’s quite likely that the “good” girls didn’t particularly need to be virgins as far as Chloe was concerned.