"WHAT IS that?" Grae asked in surprise.
As a knight himself, Grae knew that the appearance of the aura once taken in by the body of a knight and transformed into an energy reserve is colorless. And if it was released, it was still colorless to the ordinary people's naked eye.
In other words, only the knights blessed by the goddess can see, feel, and use the aura. But that doesn't mean that the aura that surrounds the world, like air, couldn't be beneficial to ordinary people.
Like how air contributes to human breathing, it goes the same with the aura as the life-supporting component of the air. That's just how important the aura is, both for ordinary humans and most especially the goddess' beloved knights.