Aura is the energy the binds magick to you. You can create with your will through magick. On Earth, this is called Chi, Ki, Ergon, Vril, or Prana.
There are many ways you can harness your Aura. Channeling Magick through your Aura is how you have your abilities on Thesis. From Elemental, Card, and Love Magick, Aura is the Ether that binds it.