Fix looks like it is in for Childhood friend A. But they way his dissatisfaction just drops off when she goes lewd-chan might be more in love with his idea of her rather than her. If she cannot get herself under control might find a way to lose despite a head start.
Childhood friend B seems to...
I don't think the blank face guy was supposed to be Shino's brother.
I think the page was suggesting Shino was trying to keep distance because she thought the Nozomi was going to leave her for a new relationship and blank face was the stand in for the new guy in Nozomi's life.
All the way back in Chapter 2 Itsuki went through Futaro's student ID to get his address. That had the picture of him as a kid. She could of known he was the kid from Kyoto since then seeing as she seemed to still have the photo of the two of them. Or one of her sisters and him depending on how...