[ She takes a seat beside Weiss easy enough, quickly working through how best to explain. There's an easy starting point, at least. ]

You mentioned Aura being the manifestation of one's soul. That term also exists in my world, but I won't say it's synonymous. In my world, the common, universal term for energy derived from the soul is spiritual energy. Among the Awakened -- that is, humans who have gained that sixth sense that allows them to sense spiritual energy and see the world as it truly is -- and generally spiritual existences such as gods, spirits, and youkai, the vast majority of special abilities the Dormant or spiritually insensitive population might consider extraordinary or the stuff of tales and myth are fueled by this energy. It gets more complicated than that past a point, but that's the basic gist.

[ She gestures as she speaks, mindful of her pacing and Weiss' expression. ]

Summoning is one of those special abilities. Although my sense is intact and my physical ability seems unaffected provided I mind my chroma, I haven't been able to properly channel my spiritual energy since I arrived.