User blog comment:Lord Loss/Monster Hunter Theory... Blog/@comment-969093-20110713091450/@comment-1758220-20110721171750

Maybe it has something to do with a magnetic organ? That way, when the Amatsu is killed, the organ shuts down and the body is no longer magnetized. And the contours and curves of his body might be just right for channeling the wind, giving him the wind aura.