Divine Aura & Epiphany Artha?

So I was paging back through the book and thinking about how cool the Divine Aura effect is, when I realized something odd. As far as I can tell, while the artha spent for a Minor Epiphany clearly goes to the stat/skill that you shade-shift, there’s no clear explanation of what happens to the artha you spend on Divine Aura.

Does it just go nowhere, or is there something I’m missing? Is there a default stat/skill it goes to?