Alex looked into his Soul Space, something he could now do without the use of his Spiritual sense. He saw the Demon Realm hanging into the darkness there, but unlike everything else in his Soul Space, the Demon Realm was in a bubble of space, with life within protected by that space.
To the beasts that were within the Soul Space, they were surprised by the sudden darkness. To them, it felt as though night had come out of nowhere, and which was surprising but not very terrifying just yet.
Alex checked the sturdiness of the barrier around the space and confirmed that it could hold its own in his Soul Space so long as he didn't do something drastic to destroy it.
Even that would take a lot of work on his end.
The next thing Alex needed to do was check whether or not he could get things in and out of the Demon Realm without messing up the barrier.