I've only played FF XIII-1 and 2 so far, but I think you're fangirling too much :D There was literally nothing to make them a couple, they barely see each other, and if anything Vanille seems the kind of girl that would like Sazh anyway, they actually spend time together, too.

Fang is a stereotypical "oneesan" type of character which is usually lusty after the main character or the toughest guy in the game. Think FF XV and the girl in armor who was trying to get in with Noctis (man, remembering her made me cringe). I wouldn't say Fang is a bad character, she's fairly nicely written but I think you're generalizing too much. What, Fang needs to be lesbian because her personality is more confident? I am all for abolishment of gender stereotypes but it feels like you people want the same standards, just without straight people in equation. "Feminine boy - ah, he must be gay. There's no way he could like women", "masculine woman - definitely lesbian, no doubts".

And there's also this thing called "friendship" but apparently you can't be best friends in this world anymore...

I am non-binary but my gender doesn't define who I am. People think about this stuff way too much. There needs to be more LGBT characters but if you want people outside of Twitter to support you, you need to drop this "Japan refuses to confirm my girl-ship, outrageous!". People who make games can't talk about things they don't feel personally interested in. Just like Persona 5 which has a male main character, just like Zelda - these games are mostly made by guys, and if you want a strong narrative, you need to make something you're personally familiar with or personally want to see.