By first impression, Jasper is the definition of confident. He seems to know what to say and when to say it, what to and when to do it, how to convince, how to woo, how to project. It seems there really is nothing he's anxious or nervous about in the slightest. He never seems to hesitate and exudes an aura that always makes it look like he knows what he's doing, even if he certainly does not. Maybe he gets this from his family, who seem to naturally carry themselves as if the world is at their feet and nothing can stop them, or it's possibly a charisma thing. No one really knows. His confidence stems from knowing his self-worth, and he'll never let anyone treat him lesser than he deserves to be treated, at least that's what he strives for.
With a history of self-confidence and self-worth issues, Jasper constantly battles with feeling like he doesn't deserve any of the things he has. A bad case of imposter syndrome if you will. Every time he succeeds in something or accomplishes a goal, he has to consciously convince himself he's deserving of that thing instead of writing it off as just luck or "someone else did it for me". Even just in day to day things, he has to actively fight against his own self-doubt. He's known how to cook since he was a kid, but he still gets anxious every time he boils water. He could solve a Rubix cube before he could talk, but sometimes just looking at it daunts him. There are so many things he wishes he could just have normal feelings about, but no matter what he does, everything feels connected to how he sees himself. It's where his need to be validated comes from.
It's not like Jasper just straight-up demands validation out loud. How ridiculous would that be? No, instead he's incredibly passive about, and sometimes slightly passive-aggressive. An example of this is Jasper asking for opinions on anything from the color to the sky to if his socks are actually the same shade of white or have his eyes been playing tricks on him the whole time. It seems he always needs another opinion to compare to so he can validate his own points rather than being confident in his own thoughts and ideas. His fear of disappointing people and being rejected are so strongly ingrained in him that'd he rather play it safe or not play at all. It's rare for him to really put himself and his thoughts out there for people to see. Things like that scare him beyond measure.
That's only a part of his inferiority complex. Like most things about Jasper, it's not obvious how he feels about himself, but there sure are a lot of hints that could easily steer you in the right direction. He has trouble sharing his true feelings for fear of ridicule—to be honest, his friends don't really help with that one—he constantly feels guilty for things that don't even correlate with him, he doesn't know how to accept compliments without deflecting it back onto the other person or ignoring them altogether, he quite literally makes jokes about his own lack of self-esteem as if that isn't a true reflection of how he feels about himself, he's hypercritical of himself, and while he avoids self-deprecating jokes because he knows how obvious those are, he overcompensates for that by making jokes about other people as deflection.
Aside from more personal issues, Jasper's a somewhat unique person. He's quite feminine and doesn't really seem to mind it, but doesn't really embrace the way people expect. The more "feminine" aspects of his personality like the way he walks, his interest in makeup, or even the activities he indulges in might be the more prominent, but overall he doesn't make it a staple of his persona to really focus on. It's just apart of him. When it comes to the way he speaks, he pretty much is the internet. Honestly, at some point, he really did end all his sentences with "periodt" just because he used it so much in text. And yes, yes he does say "sksksksk" aloud sometimes. It's totally subconscious, he promises.
Jasper's also a large romantic. There's something about a good love story that just makes him squeal on the inside (and maybe out loud too). He's always wanted a cute little love story of his own, and sometimes he applies those stories to his own life, taking the fictional situations and trying to imagine them happening in real life (sometimes tries to actually make them happen and they've succeeded once or twice). Romantic fantasies aren't the only thing he's big on. It's honestly no secret that Jasper's pretty dirty-minded, after all, that's a large part in the way he flirts. Speaking of flirting, has it been mentioned he's a huge flirt? No one really knows if it's the romantic in him talking or his need for self-validation. Either way, he's often flirting with just random strangers, simply for the sake of it. Although he'd rather prefer to be tied down and taken on a date, he'll take what he can get.
Although Jasper has a wide-set of skills he's highly proficient in, that doesn't necessarily mean he's talented in anything. He really isn't. He's had to work his butt off to get to where he is in everything he's good at, and even then he sometimes has to keep putting in that work to retain these skills. That's why he values hard work more than anything. It's such an important thing to him that he hates when people brush it off. This also makes him slightly resentful of highly talented people because they don't know the pain he's had to go through to even reach a quarter of their skill. He of course still respects them and what they do, but he wishes sometimes that they would, just for a day, lose their talent at whatever so they'd have to feel what he feels.
Even though Jasper might "fight" you as a joke, he's not a very violent person or even a very confrontational one. He likes to keep to himself and while he may have a little more bite than bark, if you ever manage to work him up to the point of having to bite, his bite can be quite nasty. Fortunately for you, he's not very easy to provoke. While he may get hurt easily, it's very difficult to drive him to the point of anger. You're more likely to make him extremely depressed or somewhat annoyed than straight-up angry. And more often not, he'd just end up being angry at himself rather than angry at you. The idea of even retaliating back would never really cross his mind unless it's as a joke. He could never find himself wanting to cause harm to anyone at all.
Although the topic of his family is very controversial for Jasper, if there was one thing he could thank his parents for, it'd be his curiosity and his willingness to try new things. Since he was literally forced to do just about everything a person can do, he quickly became apathetic to the fear of trying something new. If anything was to stop him from trying to learn another language or master a new animation software, it definitely wouldn't be his fear of changing things up. In fact, he's so accustomed to doing so many things that his newfound sense of freedom to be lazy and do absolutely nothing makes him quite uncomfortable. He finds himself pacing around his house a lot, working out, writing new songs and the like. Not doing things makes him incredibly anxious and uneasy, and while it makes for good productivity, it makes it difficult for him to avoid burning himself out.
As mentioned earlier, Jasper also has a very developed sense of wonder and curiosity. He's typically not one to ask questions directly, but he'll typically put in the time and effort to learn something he doesn't know. While it does make him uncomfortable to not know things, it's not such a driving thing that he feels the need to know everything and constantly be on the lookout for more information. It usually just dwindles down to poking around a lot, sometimes sticking his nose where it doesn't need to be, but it's usually never on purpose. He might not be constantly looking for tea, but when he finds it, he tends to keep following it. He hates being out of the loop and discussing something he doesn't know about right in front of him probably isn't a good idea. When he hears something, he remembers it, especially if it's interesting, which ends up leading him to know a lot about everyone and everything around him.