There's time travel, not time skip, because the fact she asked how many times he "came here", and he answered three, and she got that look on her face that explains everything of her situation, his power doesn't work on a linear scale, from when he first met kyara to mu there is a large implied...
Absolutely, all golden eyed people are foxes, or something else
For you who are reading this, I am commenting as I am reading this, so if at some point in the next chapters this is revealed or disproven I don't know, and it is fun to theorize