The wind magician Seiichirō Aoki (蒼軌 征一狼 Aoki Seiichirō?) is a mild-mannered copy editor with a wife and child. In the TV series, upon discovering that the battle between the Seals and Angels is at hand, Aoki secretly divorces his wife Shimako in order to spare her grief should he be killed. He impresses Karen, who eventually dies saving him in the anime. He is last seen visiting Karen's grave with his family. Aoki is a very gentle and even-tempered man and is only seen to become angry once in X, when Karen attempts to sacrifice herself for his sake. He is a wind master, with the ability to conjure and control wind currents. This is his family's gift; his nephew Daisuke Saiki has the same ability, though he isn't as strong. His barrier field is shaped like an octagon.
In the movie, Aoki is badly wounded by Nataku, but during their fight, Aoki grabs his opponent and leaps off the top of the Sunshine 60 building, killing them both.