.... THE MACHINE FIGHTER, PERSONALITY
When a person first looks at Hiro Hamada, he doesn’t look like much. Having graduated from high school at the age of 13, Hiro is classified as a genius (specifically in robotics and engineering.) The trouble with being so smart though is that it lends itself well to the streak of cockiness he carries with him. Hiro's not above using his small stature to trick people into thinking he's weaker than he is but what gets him into trouble is his arrogance that comes from outsmarting full-grown adults. Even knowing the consequences of his actions, Hiro is the type who will continue to do whatever he wants to do until something better comes along, or until a bigger force stops him.
The surefire way to entice Hiro is to provide him with something that he will view as a challenge. As someone who believes he knows more than most people he encounters in his everyday life, if a goal seems hard or unattainable he’ll strive harder to get there. As evident by his messy appearance and his even messier workspace, nothing will stop Hiro when he's onto an idea and has a deadline to meet. Hiro is a creative analyst. He puts effort into everything he does to assure he gets the best results while also allowing his designs to have a certain flare to them. Everything Hiro creates has multiple purposes and the ability to be further upgraded. He firmly believes that the only limit to anything should be your own imagination and he tends to stick with projects that are meant to make jobs easier and more efficient.
The important thing to remember about Hiro is that at the end of the day, he’s still a kid. The first thing Baymax diagnoses him with is puberty, after all, and Baymax continues to focus on keeping Hiro's neurotransmitter levels (i.e. hormones) in check. His bedroom is a collection of robots and other toys and even at the age of 14 he’s not too old to take a lollipop from a nurse robot for being such a good patient. He’s curious to the point of being nosy and generally finds something thrilling about piecing together puzzles and solving mysteries. Things like breaking and entering don’t even occur to him as anything more than methods of sating said-curiosity. Like any typical teenager, he's equipped with sarcasm and he knows how to use it. He has a tendency to panic when he lies (especially to his Aunt Cass) and can be pretty impatient when people don’t understand what he’s trying to explain the first time. He gets excited over things like Baymax learning karate or providing him gummi bears or by the simple joy of flight and it’s generally when Hiro’s alone or with those closest to him that we see him really acting his age.
When people become important to Hiro, he will fight tooth and nail to keep them close to him. It’s not entirely surprising that he’s so ambivalent about his parents’ death, seeing how he was only three when it happened, but losing Tadashi shook him to the core. It's presented throughout the film that the combination of growing up and living in the wake of Tadashi's death takes a toll on him and causes him to sometimes behave in irrational and childish ways to the point of endangerment. When Hiro's angry, it's hard to get him to focus on anything else except for his tunnel-vision and the impact of what's happening now. He doesn't think about the long-term consequences and quite frankly he doesn’t care.
Though not always chivalrous, Hiro understands empathy to a point. Having the sense of empathy though allows Hiro to ebb away his anger and grief for a short period of time to assure everyone's safety. However, overall, Hiro will always put the safety and feelings of himself and his closest ties first before he bothers with anyone else. For as mature as Hiro often presents himself, under the shell is still a kind-hearted, loving boy who’s trying not to crack. He presses his friends to fight on and not give up when things seem hopeless, even if it means just bending rules to get out of sticky situations.