I guess because Nitori is more the central protagonist of this story.
I'm not sure if I understand you, or if you understood me. What I meant was, we're seeing part of Nitori's face, like Hina would see just opening her eyes. But Hina would be seeing Nitori upside down, so it's not that.
Ehehe...good morning, Hina!Nitori, you really like humans, don't you?Yes, just a minute!Hi~na!Nitori...?You're up later than usual, are we still going to the Human Village?Well, y'know...