On one hand, you have a really calm and collected person, who is capable of assessing, taking charge, and handling just about any situation. And on most days, he's like that-- aloof but nice enough to the people he cares about, and passionate to the core about the things he chooses to be passionate about. It's the things he doesn't have the capability of control over that he sort of loses it, so we'll go from there.

Let's tackle one part of him to start out, that will be very much compromised in the setting of the game. Kid has a lot of control over himself and what he chooses to do, to the point that his self and situational maintenance becomes ridiculous. He hand-picked his weapons to mirror each other for his comfort. He wants the situation to be properly contained and handled at all time, and he's actually pretty good at it. While one of the most obvious things about his personality is how he acts out when he can't keep it all together, especially to people who don't know him, the truth is he actually got his way more often than people would admit. He's perfectly capable of maintaining a composed, yet absolutely asocial demeanor that usually tells people 'I'm not really interested in what you have to say' and if he isn't, he'll let you know.

On the polar opposite of Kid's personality is his ever-famous OCD. In the earlier part of his history, this involved painting correcting for hours on end, devotedly fixing just about everything to fall in line with the laws of symmetry, an unhealthy love of the number 8, and it was never softened for a long time just how bad he would get. There is no end or curbing once a crooked idea enters his head and he has to straighten it out. While his amount of proverbial triggers is somewhat contained in-universe, in a new setting, there are all kinds of people and all kinds of things he will not have direct control over, like in canon. It's entirely likely for things to get out of hand, especially if someone decides to pick on this particular nerve over and over. It's important to understand this sort of stimulus has to be in most situations, presented to him, otherwise he is perfectly capable of functioning.

It's important to understand that Kid's ability to keep things calm and under control and his manic obsessive behaviors are balanced-- neither is the exception nor the rule. He is perfectly capable of one but finds himself leaning into the other when a certain idea enters his head and he fails to block it out. He is never more of one than the other, though his behavior often paints him as completely obsessive-- after all, to other people, it is the foremost thing noticeable about him. Again, though, it is not the rule. While he is perfectly capable of waiting out a scene even if there's a detail that messes with his OCD off, he is just as capable of getting distracted by the same detail later depending on multiple factors; severity of the scenario being at the top. He's also not necessarily controlling of other people, just his own situation if he can and will manage to do so. He can disagree without flipping out, he's mature enough not to.

But let's get away from that for now. His empathy quotient is low, but not non-existent. When confronted with someone who was trying to fit in and could have been a danger, he opted to be kind and ask that the person go along at their own pace to fit in, and try not to rush. This implies not only does he understand, but he's been there himself, and that rushing something as really delicate as friendship never really helped anyone. He's very quick to react when someone on the team goes down… On the opposite end, yet again, he can often think of himself when creating his own comfort, to the near exclusion of anyone else (for instance, begging to do someone's eyebrows, and not caring that the last time, it took a month.) Most of the time, he falls in the middle, often thinking about just his own group and his own wellbeing. Also, if someone betrays his trust, or earns actual anger from him, there will be zero forgiveness, ever.

… which, outside of his group of his friends, makes him a veritable loner. He tends not to display an interest in people that his inner circle doesn't introduce him to, and tries to stay professional and distant with people he doesn't know well. Even inside his group of friends, he still keeps that up, though showing he can be very protective or trying to be stabilizing by instinct. He arguably doesn't make friends very well because he doesn't want to, often people will have to make the extra effort, or be a certain way that keeps him interested. It's just a way he behaves-- while he definitely knows a lot of people, the amount of people he knows positively is a limited number. He prefers to be dignified, in control, and respected, even if that doesn't go his way all of the time, which balances him out quite a bit.

If worst came to worst, he would sacrifice himself for the sake of his friends, but a lot of what he does is to try to prevent that scenario from ever happening (though he has failed that pretty badly). He does a lot more for the people he cares about than he tends to let on (but friends can often catch onto that eventually). It's all about how you view Kid. Some characters view him as the most reliable person, and other people view him as a complete and utter train wreck who is beyond saving. Some view him as manipulative, some people he's so easily manipulated that it's a joke. The truth is he's shades of everything, and while he tries to give off one impression, that effort in itself gives off many. Even in several different phases of being unreasonable and unable to handle, he still makes time to keep everything together as a prodigy and as a fighter. It takes some serious inner strength to do.