Kirei is very shy and antisocial. He spends most of his time either fighting demons o hiding in a cave that's on his grandmother's property. He's very sweet, once you get past his shy shell and he'll warm up. He's a guardian, and has his two lives still. His wings are white with black specks, and he always has his father's sword. Though he has a different fighting style than Sion, he's a little annoyed by her for her sorcery getting in his way a lot. 

EDIT: Sion is pronounced, See - aen