Hoshino was born and raised in Kivotos, a city-state metropolis on her homeworld. Her home universe hosts many sentient races, but one of the most influential and dominant is the 'Haloed', named after the very distinctive trait that every single one of them had, the glowing halo floating above their heads.
A Haloed's... halo acts as a conduit for their superhuman abilities that all of them shared plus the more esoteric esper-esque powers that could manifest in some Haloed. At the baseline using a common Human as a benchmark, all Haloed are durable enough to withstand sustained assault by small arms fire, requiring heavier ordnance to effectively wound them, and they possess stamina far beyond what Humans can achieve naturally. Furthermore, for the particularly 'gifted' among them, they'll also manifest one or more unique abilities rooted in the supernatural; everything from enhanced senses, flight, precognition, and to something as unorthodox as being able to fight autonomously while deeply asleep.
Hoshino herself is one of the most gifted of her kind. Her unique power can be described as being a 'natural super soldier'. She's prodigiously talented at martial and weapons training, mastering skills after skills related to physical prowess and combat, furthermore, she's particularly durable and enduring even for a Haloed, she can continue functioning even after 'lesser' Haloed either succumb to their wounds or fall over from exhaustion.
These talents combined with her steadfast personality makes her a natural fit as an elite fighter, an invaluable role in her home world, where despite its shiny exterior, is rife with conflict and constantly accosted by various threats from superhuman criminals, giant monsters, and last but definitely not least, corrupt authority figures.
As she used to be an
incredibly strict and harsh no-nonsense person, Hoshino didn't have many friends... up until she met her,
Kuchinashi Yume, an upperclassmen at her school, Abydos.
Though the two couldn't be anymore different; the no-nonsense drill sergeant versus the happy-go-lucky airhead, they formed an inseparable bond regardless, motivated by their shared goal of protecting their friends and families from the many adversaries of their world. They struggled, triumphed, laughed, and cried together, and for the first time in her life, Hoshino felt like she had found her soulmate, maybe, fate willing, they'd be able to spend the rest of their lives together...
...and then Yume died. Slain in one of their missions.
Just like that, Hoshino's dreams shattered into a million pieces.Until now, she never really realized how fleeting life was. One moment and they were gone.
For some reason, everything seemed just a little bit grayer now.
Though for better or worse, due to the determinator in her, Hoshino marched on, and in an subconscious attempt to remain sane, she dropped much of her harsh discipline and instead emulated Yume's relaxed demeanor.
Over the next few years, she met new people, new friends, and there was also this superintendent fellow - affectionally called 'Sensei' - assigned by Kivotos' bigwigs to clean up the city-state's mess, he's neat, if not a little bit silly, but imagine taking life too seriously, haha, who'd ever do that?
Together with these new comrades and Sensei, they too acted as Kivotos' defenders against those who wished them and their loved ones harm. Hey, this wasn't so bad, she could even say she had moved on.
But then, one day, Hoshino received intel that Yume might still be alive.
Was it a trap to lure her out by their enemies? Probably, highly likely in fact.
Would she risk it? Her better judgment said she shouldn't, but the fact remained she was already geared up and departed in the dead of night, alone.
Her new friends tried to stop her, but she gunned them down into submission. Sensei tried to talk her out of it, yet she dismissed him with a few poorly-placed jokes and empty platitudes.
They even called one of Kivotos' mightiest Haloed, one of the few that could match - or even surpass - Hoshino herself, the infamous
Sorasaki Hina the Devil of Gehenna.
They exchanged a few words, including an inquiry if she'd change her mind, rhetorical, but Hoshino could understand, Hina was just respecting Sensei's wishes for no more bloodshed, but Hoshino and Hina, they were both soldiers at heart, the two already knew...
That the only way this would end one way or another was through force.So they fought, and fought again, then fought some more, each not relenting even an inch to the other, both wholly believing they were fighting for what was right.
Their conflict eventually took them all the way on top of a moving trainAnd right there, the Iron Horus finally met her match; bested by the She-Devil, Hoshino's unconscious body fell off the train and into the abyss below...
Then at the same time, an all-consuming light came from the sky above, devouring everything.
By the time she woke up, the pink-haired girl found herself at a strange place, in a strange new world...