If you do it in reverse order, the answer to all three questions could very well be Sonata...
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Небо – угроз не слышит
Небо – ведёт особый счёт
Небо – тебя найдёт
e si ieu muoir, er mi grans deliuriers
Revan called his...
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Can you select several in F?
Небо – угроз не слышит
Небо – ведёт особый счёт
Небо – тебя найдёт
Heh, I was thinking of answering using only non-player characters, but we don't know enough about many of them for me to confidently choose the third option. Besides, different NPCs better fit different criteria.
Where do we end up when we save the world?
No.
Okay.
K: Castor.
F: Tsukiko.
M: Tria.
Небо – угроз не слышит
Небо – ведёт особый счёт
Небо – тебя найдёт
F: Igria (if Enclessia) or Erika (Thiaral), although there are plenty of candidates
M (the most difficult option): until I see her art again, I wanted to pick Alice Lit (a funny character and we know quite a bit about her, compared to other NPCs), so let it be Fiona (lol)