No One

This independent space was another such modification. It wasn't exactly a Mystical World, but it was a hidden pocket dimension that could be quickly and easily accessed by all those with high enough status. 

If one had to point toward the most secure location in all of their territory, this would be the place. In fact, even Dyon wasn't listening in on their conversation. 

Since Dyon was only a First Grade World Seer, he only had the ability to see through one universe at a time. However, this pocket space had barriers around it that rivaled the barrier between universes. As a result, Dyon would need to progress his Immortal Sense to the next stage in order to peer into their secret meeting. 

In this regard, this pocket space was even beyond Mystical Worlds which Dyon could peer through the layers of with ease.