Since she didn't have the teleport shrine near Astral Horizons, she'll need to get there manually and the only way for her to do that would be through the teleport scrolls that Stanley had given her.
But she had an idea for her to make a way to get there without the teleport scroll. After all, it would be rather awkward if she didn't have a quick way to reach her main anchor should an attack be launched against it.
Her idea was that she wanted to do something similar to what she had done in the quest where she had first met Kuromi. She wanted to use her celestial energy or divine energy to create an orb or mark which allows her to teleport to it immediately should she require it.
Plus, with her control, there was the possibility that she's able to mark other people so that she could appear beside them.
That way, if they run into any trouble, she can save them in their time of need.