The rescue - "ZIDANE TO THE RESCUE! SO AWESOME! HE SAVED KUJA AND BEATRIX HELPED! Ah, but parting is such sweet sorrow! T _ T Poor Zidane. He feels terribly guilty, but I'm proud he chose Kuja's life over Garnet."
Well I wouldn't say Beatrix helped so much as... turned a blind eye to it? It was killing two birds with one stone by letting them go - now she doesn't have to execute Kuja, now she doesn't have to worry about Zidane not acting as a king should.
Treason - "'Turned a blind eye', eh? ;) Well, I don't think Garnet is going to see like that, if she ever finds out. I mean, realistically speaking, such an act would be seen as treason against the Crown, no matter the reasons."
Realistically I totally agree with you. Even if Beatrix had gotten drugged responsibility would've still fallen on her, as she's supposed to oversee the troops to make sure there's procedures in place so that something like that doesn't happen. But thankfully in a more lighthearted fantasy story like this, there's no one who doubts Beatrix's loyalty to the throne (and no hidden cameras in the dungeon to prove otherwise).
Beatrix and Garnet - "But is Beatrix even going to at least try to be honest with Garnet? I mean, they're so close..."
IMO Garnet's actually closer to Steiner. Her relationship with Beatrix always felt like a professional one to me, whereas Garnet and Steiner's was more like an uncle and niece (or even a father and daughter, though I doubts either quite sees it that way) - he has that whole "You're not good enough to date my daughter!" vibe going. Part of it is that he is noticeably older than Garnet, and that he's apparently also been something of a caretaker of hers for at least a few years.
Also as far as Beatrix, in chapter 12, when she goes out to find Zidane hiding in the garden, she keeps thinking it's not her place to interfere in his relationship with Garnet (although she does, even while saying she shouldn't). But I was trying to keep something of a professional distance there, where she's dying to give her opinion, but knows it's ultimately her job to keep her mouth shut and provide support instead.
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New chappie:
http://www.fanfiction.net/s/8057142/18/ Hoping chapters will start coming steadily now that I'm done with my move : )