Idan and Arabel were very grateful to Alois and Liam for showing them how the aura works.
Eulalia and Milica, in turn, showed them how to use mana, but did not tell them about aura. From the way Eulalia listened to Alois' story and showed surprise, it was obvious that she did not possess an aura.
Milica probably knew how to work with her, but they hadn't shown her their skills until today.
At that time, they didn't understand the difference between aura and mana very well, and they didn't pay much attention to it.
Since Milica belonged to the higher realm, she should know about aura.
Putting aside the question of asking their master about aura for later when they returned, the group continued on their way.
This was only the second day after «Reset», and they still had five days left. They planned to spend two of them retreating back to the city. It turns out that, apart from today, they only had three days to get to the central layer and explore it.