Her backstory is that she's from a private all girls' school while the other gay character in Valkyria Chronicles is a stereotypical okama who LOVES muscly dudes. I guess that's still pretty good by 2008 standards, and better than Valkyria Chronicles 2 where there wasn't even a hint of same-sex romance despite all recruitable characters having full subplots of their own in that game. They did make sure to have a dude in love with his sister though 
On the other hand VC2 did have a non-gender conforming character, a male-presenting woman who even used the male base character model though her backstory ended up being that she had been brought up as a boy by her father who had wanted a son, which seemed a bit iffy to me. Not that I should be expecting too much from dated anime schlock
I mean especially back then Maria-sama ga Miteru was a cultural juggernaut for lesbians in anime, everyone going to private girls schools was kinda gay coded because it's just girls playing around, but when they grow up they'll find a man and settle down into proper wives.
Yeah, that's what I was getting at. I'm not sure how queer either of these characters is intended to be read as. I think it's telling that they avoided having any potentially gay characters in the sequel where there's several romantic subplots between characters.