Ser Jamie Casterly, the Kingslayer. It speaks for itself doesn't it? He is an arrogant, arrogant man who has no honour to himself. He thrives off of pissing people off and rubbing people the wrong way, he is the most dishonest man we may have seen.
Everyone hopes for Jamie Casterly to get his comeuppance, Ignis wishes that his brother knocks him off his horse during the joust and. However the problem with Jamie Casterly is that he's just too good. He's too good of a jouster and he's too good of a swordsman, so no one can touch him. Ignis's brother fails to beat Jamie and Jamie makes his way all the way up to the finals where he wins. You have got to hate him, look at how handsome he is and look at how smug his face is. He's the idea of a perfect knight Ignis thinks, he'd be a perfect man but he's a terrible, awful person and a complete subversion of his skills and looks. He's very easy to hate. No one except his family respect Jamie, Loreon tries to recruit Ignis to go and rescue Jamie but Ignis sternly refuses; he is not going to help that man.
He's a very cruel person and perhaps a classic bully, mocking Valerie Allyrion at every turn he can get, mocking her womanhood by pretending she was a men and feigning surprise when he finds out she's a woman. He games with his men to see which of them will be attacked by her first; mocking her father for being wheelchair bound amongst MANY other things. Jamie's tired of all the common retorts such as 'kingslayer', he's so arrogant he wishes that people can come up with better and more rare insults as he has gotten bored of his old nickname.
But he seems stuck in one place, stuck in a series of bad choices. He doesn't have much control on his life, his father Tywon decides who he gets married to and Jamie doesn't have choice in that. His father plans to marry him to Rhaenerys and doesn't converse with Jamie at all on what he thinks, Lord Tywon and Aeyron decide amongst themselves to send Jamie out to rid The Hunter's Gift of bandits as a result of Ulthor Young's rebellion. He doesn't want to do it, he had nothing to do with that war but he feels that he has to clean the king's own mess for him. His lover Jayna Casterly seems to overpower Jamie too, she emotionally manipulates Jamie by telling him that his father is disappointed by him and that Loreon envies him. She's the only one that truly loves him, and she's the only one that loves him she suggests. Jamie has nothing else but Jayna according to her, and if he removes her he'll have nothing left. Jayna compares him to a drunkard, she knows that he'll keep on coming back to her no matter what and despite Jamie's disagreements she's always refusing his statements. He's also stuck by his monicker of Kingslayer, it defines him for life and is what people call him - it's the first thing people say and think. We see it when he announces to the village that he has killed The Best Friends, a good and honourable deed but when the townsfolk find out he is The Kingslayer, they curse him and retract their praises. It seems, whatever Jamie does he cannot outlive his notorious deed. One can also say that he's trapped by his father, Lord Tywon possibly outshadows Jamie. When Jamie interrogates the Lord of Ashford Jamie's threats don't seem to work as the fat lord continues to argue against him but when Jamie brings up his father's name, Lord Granger cowers away and doesn't argue any further; people live in fear of his father but are not affected by Jamie's prescence. When Jamie tries doing the same thing to Ser Hoare Lorch, it fails terribly. He repeats his father's name multiple times which only serves to piss Hoare Lorch off even more - he becomes enraged that Jamie can get away scott free by saying his father's name. In this case his inability to mean anything without his father means that he suffers, his arm is broken and maggots are thrown into it. He learns here that he needs to become his own man, he cannot live in the shadow of his father and live off his legacy - Jamie has his own legacy but he is scorned. He needs to become something that has an impact on people, not just making people's face shrivel up. Jamie needs to become his own man.
And he has a storied backstory, wrought with self-doubt and skills. Jamie was the youngest knight to join the Kingsguard, so he has idealised expectations of what it was to be a knight of the Kingsguard. He remarks that people loved him earlier, before he was the Kingslayer and that they turned on him all of a sudden, for doing them a favour by killing the king they all hated anyway. He's deeply traumatised by what he saw as a young kid, watching men be burnt alive by Orson Casterly - everything went the way it shouldn't have. His dreams had turnt into nightmares. He truly has mailce for Orson Casterly, and what he was put through, yet in the public's mind he should be scorned because he finally rid the world of something evil like that. He doesn't understand. His biggest problem is that his backstory is wrought with moments of pure evil, and moments of pure magic. He contrasts Orson Casterly's wickedness, with Orson's wife - Syrell Hightower and her purity. Syrell reminds him of why he joined the Kingsguard, to serve under someone so good and to be so proud of what he achieved. He's humbled by how down to earth she is, but alas his dreams become nightmares as Orson again rips up his fantasy tale and corrupts. He talks about Orson raping Syrell, corrupting the image of purity with pure evil, he tries to do something but the other Kingsguard stop him - they are too protect her but not from him. Jamie's thinking is deeply questioned, he's supposed to be the highest level a knight can be but he can't stop a rape - one of a knight's duty is to protect people from harm, yet he's being told by all these fellow legendary knights he shouldn't do his duty. These are men that he idolises, his brothers, and they're telling him this. His logical thinking is fractured. Of course we also learn that Jamie killed Orson Casterly to stop him from exploding all of King's Landing, he has perhaps done the greatest honourable feat in history. Sacrificing one life to save hundreds of thousands, yet again, he's scorned. Why? Why is he being scolded when he's doing the right things? By that moment, Jamie's lost it. He's given up on the ideals of a knight. If this is what it is to be a knight, to do horrible things then he'll embrace it. He'll embrace the villain everyone wants him to be. Jamie has been broken.
He's in conflict with the idea of himself, and the idea of what he should be. He plays the part of a villain, but does he want to be a villain? Jamie tries doing honourable things at time, he defends his brother and reassures him that he will always support him and have his back no matter what his cousin or father say. He stops Valerie Allyrion from being raped, putting himself on the line for her, he attempts to stop Syrell Hightower's rape. And he also questions Lord Granger on why his citizens are being starved into corpses. There's some part of him that's stuck, that wants to do good things but it's stuck under layers of contempt. I've already recounted on all the terrible things he does, but when Valerie calls him weakminded for giving up on the people, he takes a moment to look around the room and when he notices that there are a lot of people in the room; he resorts to the dishonourable person he embraces and says "whatever you say Brute". It's sad, he feels he needs to fit in with everyone else and can only question himself in his mind or when he's alone with Valerie.
There's a good man stuck in Jamie Casterly. He's gone through trauma, he's been changed by the events around him. The people have given up on him and he's given up on himself too. But Valerie Allyrion is helping him question things again; what will become of him? Is he going to become a good man, or is he going to be stuck as a terrible man?