Born Haruki Yamashita, Aquila is a human of Japanese descent turned cyborg whom didn't nessecarily have too much he wanted to achieve prior to the Great Nuclear War. However, he still possessed a high level in engineering and as such, commonly assisted his friend Atsuro Koyama with his strides. However, they had heard about the potential outbreak of war, and out of fear, Atsuro decided that he would relocate to the part of the world that would be the least affected by nuclear fallout. Haruki initially thought Atsuro was crazy for this but he and his younger sister Suzuka had gone with him anyways.
Turns out that Atsuro wasn't worked up for nothing and the three spent the in an underground base WELL secluded from the rest of society. The amount of technology they took with them was somewhat limited compared to what they had before, but it was enough for what they really were trying to do. Atsuro, Haruki, and Suzuka eventually converted themselves into cyborgs in an attempt to making surviving miles easier. They were overall stronger, felt less pain, and needed not to replenish energy or breathe, as well as achieving biological immortality. However, they could still be killed by severe wounds, decapitation, or pretty much anything that would badly damage their mechanical augmentations. The remaining materials were used to make weaponry, due to the amount of zombies left from the aftermath of the war. Haruki given a highly modified sniper rifle, Suzuka given a highly durable greatsword, whilst Atsuro merely carrying a knife and a Glock 18.
Every day the three would go out and kill whatever zombies headed too close to the surface which their base was located. Eventually a metropolis, now known as Crestfall, had been established above them and it indeed contained survivors, and it was then where Haruki had heard about these people known as the "Scarf Heroes ". Atsuro believed that they shared similar goals and it may be wise to seek them eventually. Unfortunately, several days later, the three were attacked by a group of thugs whom desired their technology because there was little technology of the past was left, and neither were enough people intelligent enough to recreate it. Upon refusing, the thugs attacked, and Atsuro was ultimately pinned and repeatedly stabbed. Enraged by this, Haruki demanded Suzuka to take down the thugs with no remorse. She reluctantly agreed, although Haruki did most of the work.
Haruki claimed to briefly lost control of himself in a literal sense. On the brink of death, Atsuro had told him that he added a crisis mode known as Overkill Mode that would activate if he was either badly damaged, enraged, or insane. Initially, Haruki was a bit mad over how inhumane the whole premise was since he would lose most control of his actions, but considering the nature of this world, he let the thought go. Haruki was left depressed and his sanity was slowly lowering, but he valued the lives of others and decided to assist those who really needed it.
Oh, and the Aquila name actually came from Suzuka, since she felt that Haruki needed a cool nickname. Suzuka didn't receive one since Haruki thought the idea was rather dumb, but he eventually did stick with the Aquila name.
Aquila an introverted individual, and can generally be seen as straight up cold. He is a cynic that despises what humanity had done to itself and isn't too fond of those directly responsible for the war. However, he is willing to help those whom cannot fend for themselves, and does so solely because he thinks it's the morally right thing to do. Despite this, Aquila is still a morally grey character, unafraid to resort to taking the lives of his foes in a fashion that can be deemed as literal overkill. Aquila is also a pragmatic individual, mostly focusing on efficiency rather than trying to look cool or honorable, and the only time he would start fights himself is if he is pretty much guaranteed to make it out alive and intact. Curiously enough, Aquila prior to the SH timeline was still an introverted person, albeit he was far more open, as what humanity had done to itself during and after the war potentially turned him into the cynic he is today.
This is a feature which Aquila possesses. It serves as a crisis mode that primarily activates if one is heavily damaged. It can also be triggered by anger or insanity. One can tell if this mode is triggered if the eyes glow a bright white and electrical energy is radiating around Aquila. While it does improve combat quite a bit (defenses noticeably decrease in exchange higher speed and better combat proficiency), this unfortunately leads to him having limited control over what they do, and may lead to destructive and/or catastrophic results.
A modified AWP sniper rifle and Aquila's primary weapon. It was made using whatever technology was left over after Aquila, Suzuka, and Atsuro became cyborgs, and shoots photon-based projectiles designed to pierce through heavy equipment.