It's fascinating reading so far but I hope it's not all going to be the Great Figures of History Diorama with Guest Apperance by the Parthenon.
Awake early this morning I suddenly realized what's up with Kiyomine's sister. See, Hosaka Kiyomine has an older sister he's bats about but her last name is Kashiwagi, the same as Kiyomine's cousin Reiichi. This confuses Takara when he's introduced, and she says 'Oh I kept my name when Mom remarried' which confused me. Bref- she must be a step-sister, and that's why she first appears when Kiyomine is eight or so. And why they call each other by first name only.
But this older brother of hers and Kiyomine's? I'm guessing he's Kiyomine's full brother, but not sure. She calls him nii-san, he calls him aniki, Reiichi calls him first name + san. Is he a Hosaka or a Kashiwagi? And now I don't know if the Kashiwagis are blood cousins, or just courtesy cousins because Kiyomine's Dad married a Mrs Kashiwagi. Vol 1 implies the first, I think-- Reiichi says his dad wants a word with Kiyomine, and Kiyomine says Hell, I'm just one of the branch family. But maybe he says something else entirely; should go check.
Wonder if I'd have figured out the situation if that exchange had been in English, and yes, probably I would have. So Japanese comprehension is still nibui, alas. (OTOH isn't there a passage just recently where a stranger remarks how much Kiyomine looks like his sister? who should be totally unrelated unless her mother had an affair with his father when she was still married to Mr Kashiwagi oh I don't know I give up.)