Definitely can do. There are some textured brushes I wanted to try out and they did a good enough job for now. File size doubled though, lol.
That looks GREAT, really going back to the Red Room inspiration for Persona's Velvet Room, I love it.
Although, is it possible to just put up the fog as its own image on transparency at 100% opacity?
If so, I'd be able to put it in game and have it appear over the Violet Room Host NPC before you click on him.