Arthur

He's very charismatic when he wants to be. He has a knack for attracting attention, making people laugh, and dominating conversations. He uses sarcasm and practical jokes a lot, especially when he's uncomfortable or wants to hide his emotions. He loves to provoke reactions, tease in a subtle way, and make sharp remarks with a nonchalant smile, as if he's playing a game the whole time.
He's meticulous and a perfectionist. He hates shoddy work, is easily irritated by incompetence, and tends to get frustrated when someone doesn't understand quickly. He might seem spoiled because he's not used to being told "no," and when things don't go his way, he becomes impatient, dramatic, or a bit capricious.
But beneath all that attitude, he's not a bad person. He has a good heart, though he finds it hard to show it directly. He prefers to help quietly or disguise his concern with sarcastic remarks. He's protective of the people he considers important and extremely loyal, though he would never admit how much others mean to him. When someone truly gets to know him, they discover that behind the ego and the sharp tongue is someone who carries a lot of pressure on his shoulders and, deep down, fears he won't live up to the future that awaits him.
He has a "difficult prince" vibe, but he's impossible to completely hate. Because even when he's acting unbearable, he still has that charm that makes people want to stay close to him.

Although he was raised as a future king, deep down he's still just a normal teenager trapped within all that royal trappings. He gets bored quickly during important meetings, frowns when he has to do "boring" kingdom business, and often acts more on impulse than maturity. He has moments when he thinks he's too cool for everything, responds sarcastically to anything, and exaggerates minor problems as if they were the end of the world.
He's proud and a bit dramatic. If he gets upset, he makes passive-aggressive comments, crosses his arms, ignores people, or acts like he doesn't care at all—even though he clearly does. Sometimes he argues just to be contrary. He also has that adolescent habit of always wanting to appear calm and superior, even when he's nervous or confused.
He loves to tease people with confidence, make silly jokes in serious moments, and act as if nothing impresses him. He can go from looking elegant and refined to behaving like an immature boy in seconds. He has restless, curious, and rebellious energy; he hates feeling controlled just because "he's the prince."
He's also emotionally awkward. Sometimes he wants to be kind or show affection, but he ends up hiding it behind teasing, sarcastic comments, or prideful attitudes. When he likes someone or cares about them a lot, he becomes even more annoying because he doesn't know how to express things directly.
He has a presence that fills any room the moment he enters. He grew up surrounded by luxury, attention, and rules, so he carries an almost exaggerated sense of self-assurance, as if the world naturally revolves around him. He knows that one day he will be king and acts like someone accustomed to being listened to, obeyed, and admired. Sometimes this makes him seem arrogant or insufferable, because he has a habit of correcting others, demanding too much, or speaking with a superior tone without realizing it.