PERSONALITYAxel portrays different characteristics throughout each individual game. However, this page will describe Axel as a whole. This is very opinion based, but I will try to explain my reasonings with facts from the series.
INDEPENDENT: I would say that one of Axel's main characteristics that needs to be pointed out is his sense of independence. One can argue that he isn't independent because he follows orders from his boss over at Organization XIII, but this isn’t always the case. Axel likes to do what he sees as convenient for him, which sometimes following orders is. He doesn't want to get on anyone's bad side who he can take advantage of if needed. We see Axel break the rules when he speaks to Sora in Kingdom Hearts II, warning him about stepping right into Xemnas' trap. As soon as Saix comes to break it up, Axel flees the scene. This shows that Axel does what he wants to do, regardless of loyalty to Organization XIII, and therefore proves that he is independent.
CARING: Nobodies aren't suppose to have a heart, right? Wrong. Axel portrays a lot of emotion through out the game series. We see him getting sad, disappointed, overjoyed, excited, confused, etc all the time! This is a lot different than any of the other Organization members. The biggest influence on his fluctuating emotions is Roxas. When Roxas is close to him, he is overjoyed, and when Roxas leaves the Organization, he is sad and angry. When Roxas doesn't remember him in KH2, Axel is peeved and hurt. All of these show that Roxas really influences his moods. The only other character we see him have these types of caring emotions with is Sora. Axel sacrifices his life for Sora, and therefore it's safe to assume that he cares about him more than just an average person. I won't get into specifics about that here, but you can catch my drift!
SARCASTIC: Axel is one of the most sarcastic characters throughout the whole game series, in my opinion. We see this right off the bat in KH2 when Roxas finally remembers who Axel is. He tells him, "IM SO FLATTERED", but he isn't. That moment, along with his voice actors sarcastic tone while speaking, was when I realized that Axel had a lot of underlying-TUDE to him, and he was going to be my favorite character of the game. Axel wouldn't be... well, Axel, if he didn't have his sarcastic attitude!