Sora is from the game Kingdom Hearts. He is the weilder of the Keyblade, a key like weapon which is able to lock/unlock any lock.
He is a 14 year old boy searching for his friends. While searching for Riku and Kiari he meets Goofy and Donald Duck, who are searching for The King. With his new companions he travels through different worlds, like Halloweentown, Wonderland, and much more.
Sora returns to continue his journey. Sora and friends find an odd castle after following a black cloaked man. The man says that his friends,The King and Riku, are inside. This sets the stage for the adventure through memories in Castle Oblivion.