Yuuma commands quite the presence due to his deserved self-confidence. An aspiring fire-fighter, he carries himself with discipline and strength, his fitness, coordination, and reaction speed all extremely impressive, and he's incredibly hard-working (at least when it comes to physical activities), leading him to be adept at many sports. Consequently, this has made him popular in his school years. As he has a relatively good life and a planned future, he has a hard time understanding those that recede to the virtual world, viewing them as pitiful and lacking in the strength needed to become successful in the real world.

Another quality of his is that he's a sponge -- he learns from others constantly, and it's one of the reasons he's well off. He learns from the mistakes of those around him equally as much as he learns from their successes, adjusting himself to become better in anything he does.

While he used to be incredibly outgoing and friendly, his sister's death tempered his outgoing attitude significantly, giving birth to a darkness inside him that he keeps shut away as tightly as he can. He isn't quite a jerk-head recluse yet, and will greet everyone who speaks to him with a kind -- if a little small -- smile, but his patience for those he views as 'weak' is far shorter than it used to be. It isn't uncommon for him to get angry with people who can't keep up with his pace. Due to his inherently kind nature, however, he usually immediately feels guilty after an outburst and will apologize profusely. Along with this, he is now far more prone to act impulsively, going against his usual calculated self, and often feels the temptation to do wrongs, in whatever form that may be, if it gives him some sort of advantage. For now, that's been limited to considering stealing a wallet, or sabotaging an opposing players equipment, and the like.

Yuuma's defining trait is his drive. The boy is driven, for better or for worse. In the real world, it's been working for him, putting him in an excellent spot in life. But with his newest goal of shutting down Brain Burst, his drive could end up running him into deep trouble.

Yuuma lived a normal, active life with his parents and older sister. When the two were younger, Yuuma and his sister, Hikari, adored each other, always playing together and learning from each other. As they grew older, however, they drifted apart a little, as siblings do, the primary cause of this being her getting a boyfriend in her first year of highschool.

Yuuma got over any resentment he felt towards the boy for taking his sister away fairly quickly, growing older himself and focusing on his own life and friends (and helped by the fact that the boy was pretty cool). Yuuma did notice how Hikari began to ace school and excel in sports. It was strange, since that had always been his thing, but she seemed happy, and it pushed Yuuma to work harder to live up to the high standards she was setting in the Mori household, so it was okay.

As he reached his highschool years, however, her personality underwent an unsettling change. She, slowly but surely, became a skittish, exhausted-looking, and snappy person. Concerned, he tried to talk to her and find out what was wrong, but she pushed him away even more, to his confusion -- the two had always trusted each other more than anyone else. If she couldn't tell him what was happening, just how bad was it?

It all lead up to her death one snowy evening after school. Officially recorded as a suicide, she had apparently thrown herself off a bridge, breaking through the ice that covered the water far below.

Devastated, Yuuma managed to internalize his feelings on the event scarily well and continued with his life. He was changed, but not as much as one would expect. Part of the reason for this was his desire to be strong for his parents, who both were broken by their daughter's death. The hardest part for the boy was all his schoolmates offering their condolences. He hated it. People viewed him as weak and fragile for the first time in his life.

So he worked harder at everything, doing all he could to never show a sliver of weakness. He'd be so impressive, so perfect that his peers wouldn't look at him with pity in their expressions, and his parents would be forced to take their minds off of his sister to acknowledge his accomplisments.

It would only be several years after the event that Yuuma would recieve a message from Hikari's old boyfriend and learn the truth behind his sister's death, and consequently of the existence of Brain Burst. (This encounter will be my introductory/first post for Yuuma. Basically, the boyfriend introduced Hikari to the game, and she rose up the ranks, eventually becoming a King and having a huge target on her back as a result. A small group of people threatened her, saying they would kill her if she didn't let herself be defeated. Unwilling to have her avatar deleted and Brain Burst uninstalled, she didn't comply and grew paranoid due to the groups increasing aggressivness. Ultimately, one of the group members made good on the threats, sending her off the bridge to stage it as a suicide).

The revelation causes Yuuma to completely change his focus in life, dedicating himself to bringing Brain Burst to an end through whatever means necessary, convinced the program does far more harm than good to its users.

Yuuma's primary ability is a limited shape-shifting, granted to him by the strange substance that his avatar is made of. His base form is the one pictured, and it is relatively constant, but he can shift his limbs into various shapes and objects.

At Rank 1, all this essentially does is give him greater melee range by allowing him to extend his limbs. As he increases his rank, he'll be able to change the density of his body at will, allowing for devastating strikes and greater mobility, and will gain the ability to create more and more complicated shapes, such as functioning guns. (Think Alex Mercer's and James Heller's powers from Prototype, basically)

The versatile nature of the alien-like substance of his avatar also causes it to automatically take on the properties of things it comes into contact with. For example, if Yuuma gets electrocuted, his body will become charged with electricty that he can discharge. If he gets stabbed by a steel blade, his body will begin to become as hard as steel. Yuuma's avatar will revert to it's normal state after every match.

Adaptibility is the name of the game for Yuuma's avatar, which goes hand-in-hand with his generally calculating fighting-style. Meaning the longer a battle goes on, the better Yuuma's odds of victory tend to be.