What is with this guy? He's pyscho, deadly and wants a human to defeat him? Is this guy okay in the head? I mean, he's probably powerful enough to take over an entire world on his own if he wanted to; Thomas
Alucard, once known as the infamous Dracula, is Seras's Vampire master, the one who changed her, he is a master of the dark powers of vampires. He is a forced servant of the Hellsing Organization. He can change his body to hundreds of forms, and asides from the keyblade and light based powers of Seras, he has all of her powers and more. He is one of the most powerful beings in the universe, and the only vampire that is totally immune to the power of Kur. Alucard desperatly wishes to fight a worthy opponent, completely human and to be bested in combat.
Thomas did this feat when Doofemsirtz took control of him and was forced to engage Thomas in battle, Thomas barely comming out on top, destroying him with Power Star Oblivion. He later revived at some point, and is now again a forced servant of Kronos, at one point confronting Alex Storm and is known to have a hatred for John Victoria as well as Percy's pet, Mrs. Ol' Leary, Thomas and all of Greenia. One of his goals is to get Seras back under his influence, as he has feelings for her. His anger ended when he was defeated by Tsukune Aano, whose power came from his close connection to the vampire Moka, which also kept him from perishing. He then decided to go out on his own and train, until the day he could redeem himself, with only Tsukune, his "harem" and Tonto knowing of his continued existance.
In the far future, he is still alive, and at one point defeated Zeus, but Anderson got in his way. It was shown at some point he had aquired Harry Potter style magic abilities from Kronos. He later found his way to a mysterious new world of vampire and became its leader after many battles. Later saving Tonto from a meteor based death, he told him to contact him in the time of greatest need, where he will proove without a doubt of his redemption.