On the way back to the castle, Bai Zemin and Seraphina again covered their bodies with those big cloaks in order not to draw too much attention on themselves.
Different from Earth, the average level of humans in Eventide World was higher and most of them had one or two skills either active or passive apart from the skills one could easily learn such as Cooking or Mechanic. Therefore, it was easier to be caught upon activating a stealth skill not to mention the fact that to avoid trouble it was forbidden the activation of skills such as Invisibility.
If a soul evolver was caught using Invisibility by the defensive systems of the city or by a guard then they would be locked up and interrogated until their innocence was proven. After all, why would a person hide inside the city where there were no enemies?