"I'm not trying to teach you how to find one specific person out of the crowd. Later, maybe that will be a useful skill to hone, but I believe you have some skill in that already. We are trying to teach you a new application of your power, not yet making your existing skills stronger," Rukia explains, stepping lightly around Castiel and watching the even expression of his face. He's an interesting student to work with, obedient, but with a tendency to step forward in a direction she hadn't been intending.

"My energy is different than that of human souls, yes. Instead of visualizing it as a brighter color, try to train yourself to see them as different colors. It will make things faster in a pinch. You won't have to 'look close,' as you say, to know when a soul is different. My soul and Dean's soul are similar, because we are both shinigami. In the academy where I learned, we were taught to view these souls as red," Rukia explains, straightening her shoulders. "To pick red out of a sea of white becomes an easy task. Can you see? Dean and I are not the only people in this city who are spiritually powerful."