Doctor Caesura (pronounced 'KAI-sura')
He is the blond dude in this comic.
No, the pic is not mine, but ever since I read this comic I cannot get the blond-Doctor mental image out of my head.
Doctor Caesura is a quiet individual, although not from shyness or low self esteem. He simply does not like to raise his voice or make overly dramatic overtures. People say that they have rarely seen a man who is kinder than Caesura; the Doctor is gentle to everyone and everything, save for people he believes are his enemies. He has been known to bring in and shelter nearly anything, whether it be kittens or a near-insane girl he found lying in the streets of Traverse Town. Many of the scorned people find a friend in him. Caesura does not discriminate and he actually seems to welcome uniqueness.
Despite this, the Doctor can be quite fierce when angered. He comes from a place called the World of Mana, which has some of the best magic-users ever known. He uses every type of magic to fight, and when you harm someone he cares about he will go all out on you. And because he's a Doctor he knows exactly where to hit to take people down as quickly as possible.
Caesura originally came from a world where magic was abundant as water and air. This is called the World of Mana by many since there are few recordings of the actual name of the world. It's inhabitants never knew of Heartless or any such weapons as the Keyblade, but they were very aware of the forces of Light and Dark and magic. Caesura spent his time studying to be a doctor, which in his world required both a proficient skill in magic and more mundane practices. But, despite this, Caesura always loved to travel and wanted to got o different worlds one day.
He managed to do that when adventurers came to his world on a Gummi Ship, an he persuaded them to take him along when they left. For a few months they traveled together, then once he got enough money to buy his own ship they parted ways and he spent his time hopping worlds. It was on one of these trips that he found Anastasia in Traverse Town, half insane and very sick. His doctoring instincts kicked in and he nursed her back to health, then kept her with him as company since she obviously had no idea what to do with himself. They now travel together with Caesura, and he's teaching her some of his world's magic.
Caesura often uses magic in his battles, but even he gets tired after a while. Whenever this happens he cranks out the halberd.
It is a weapon he forged himself back on his world, and he imbued different elements in it to make it almost unbreakable and able to damage enemies much more than a regular weapon. For example, it can damage Heartless and Nobodies.
If the Doctor had a theme song, it would be A River Flows in You.