^It's like a last-wish-thing. The moment he died (prolly got hit by a car or such) he wished he could be at least one more time with his owner. And the girl also needed that kind of closure to become stronger.
ow :O ok I get that :v thanks for the explanation!
i think that he did die because a cat's lifespan is not that long and that his lifespan just ended. I think he ran away because he did not want minori to see him die and he became a human to fulfill his final wish.
I didn't follow the 3rd story, is the black cat dead already? O.o why does he disappear after he turned in to a human on fullmoon? :O