Short version is that she's the heiress of a big company that's been run unethically by her supervillain of a father, ran away to find herself and become a huntress and just make her family name not be synonymous with awful. high strung, lil bit of a bitch, life loves to knock her down a peg or two because she's the serious one, but she's got a good heart
I imagine they'd probably have a somewhat similar trajectory to Weiss and Ruby ... namely that Weiss initially dislikes her because she views Ochako as someone who isn't taking things seriously enough, Ochako probably thinks Weiss is a dick and maybe just a little bit intimidating because of the irritated Ice Queen aura she's got ...
and then seeing each other do their thing, getting to know each other better, and being forced to fight side-by-side odd couple style eventually clears the air
And honestly?? They'd be super fucking cute
hibiki would fit in very well in a mha ausinging mecha lesbian magical girl babyyyyyy—silently holds up symphogear