if no development happens while they're alone i'm going to be pissed but i wouldn't be surprised either. also wouldn't it just make more sense to have them spend the time alone when they were lost instead of leaving them behind again?
@R-Mod Katai-kun could have been a one-off, plus it's been pretty one-sided. It's fairly uncommon for a harem MC, let alone a SoL MC, to have a male member and it's usually a josou