At this point, I think the word choices in the first chapter were a clever marketing tactic to get eyes on the manga. And I mean... it worked, since I'm still here, at least? And feeling oddly hopeful about how the story may develop. Still would've preferred it not start off on a terrible foot, though.
Ao liking both boys and girls but falling for a trans genderfluid Momiji (girlfriend) + Kouyou (boyfriend) (the "Momiji & Kouyou System"? accidental plurality in this work?)
I love this hypothesis, since I'm deeply amused at the coincidental similarities to some character developments in a tabletop RPG I've been running. (They weren't an accidental system, as it was a carefully considered character concept, though. More talking about their prospective girlfriend wondering "Do I like boys or do I like girls?" and landing on "Yes." During a clothes shopping trip, no less...)
There were some pretty major differences but I'll stop here so I don't ramble about off-topic things more than I already have.