Spoiler warning: Watching Chihiro's releases





I agree with the Nagi situation. It was explained that Kei and Chihiro had more or less adopted Hirono as a brother. Kei and Hirono remained close after Chihiro's accident, while Kei kept her distance from Chihiro. Perhaps Nagi was abroad at the time, and she might have called him once, I don't remember. The large age gap between the two raises that possibility. Still, rather cold of her to abandon him for so many years, but from the flashbacks, that's just the way Nagi is.

What I am beginning to wonder now is whether the Nagi/Yuu/Yuuko love triangle will resolve itself during the flashback, or in present day. It seems like the flashbacks are establishing all the relationships, Nagi is just as secretly possessive of Yuu as Kei was of Hirono, Yuuko is really weird, etc. This may lead up to Yuuko's eventual death (I'm sticking with her being a ghost) and how hurt Yuu became over that.

Then we will return to the present, where Nagi is in town for a rare occurence, right before she leaves for Australia. Perhaps we will see Yuu learning to love once more, and join Nagi.

As for the Mizuki storyline, their relationship is...was progressing very rapidly, but now Kuze is still attempting to blow her off. We know that she will get him to have sex with her before he dies, but I wonder now progress can really be made in terms of character development, given their little "CPR" sessions.