I can't remember all the details, it's been a while since I read through it all, but hasn't Hina been pretty firmly in the "If Hana knew how I felt, she'd never talk to me again" camp? Like, she's annoyed with her old coworker friend and wants her to go away, but more than anything, she emphasised the "I'm Normal" bit because she's terrified that Hana will hear all this ex business, get the wrong (actually right) idea, and be all grossed out and start distancing herself?
Also have a vague suspicion that Hina really did have feelings for Maiko, was in a relationship with her (or had an extremely gay friendship) only for Maiko to get spooked, cut Hina off, and is now waltzing back into Hina's life casually talking about their past as if it's just some running gag they had carried over from a photoshoot? I'm not sure. There's a lot of extraneous details and foreshadowing if there's really nothing more to it than old friends who joked around a lot before falling out of contact.