"She's not here."
"What do you mean she's not here?"
Rainbow Dash snapped back awake. She still wasn't good enough at balancing her powers to keep herself both in the dream and receptive to the outside world when dealing with too much stimulation on one side. She slowly opened her eyes, holding back her desire to exhale. "She's not here," she said again, forcing calm in her voice. "Not close at least."
Luna's body was on a bed in the middle of the room, right in front of Rainbow. Celestia sat quiet near the head of the bed, Twilight near the other end. She was the one speaking. "Where is she then?" She also evidently was forcing herself to speak with more calm than she felt compelled to.
Rainbow chewed on nothing for a bit, thinking about how to put things. She swallowed, then spoke again. "Imagine a deep sea. Or an ocean. It's not quite what it's like, I don't directly see it, I feel it more than anything. Imagine you're deep underwater, but there's still enough light to see around and you can still see the surface if you look up. There's nothing around for as far as your eyes can see, and you can't see the bottom either." She took a breath slightly heavier than the rest, looking down to the carpet as she tried to focus. "It's different from how it usually is. I'm not sure if I'm seeing the surface of her dream, or the surface of where her dream is."
Twilight was confused by that. Celestia less so. "Where her dream is?" the first asked.
"There are spaces," Rainbow replied, "within the dream world. Spaces dreams sometimes occupy. Sometimes they're the dreams of places that exist here as well, like the Everfree. Sometimes they're different, they're something else that exists as a part of how dreams work, but I've never learned much. But I think Luna's dream has ended up in something along the lines of the latter." She scrunched, then spoke again. "Sort of. What I feel is happening is that her mind is there, but her dream is... It feels like her dream and the dreamspace she's in have melded together. Like the bubble around her mind is open and she's... It's hard to explain."
Twilight looked pensive, but she slowly nodded. "You know more about this than I do. What does this mean in terms of finding Luna, then? Can you find her?" They didn't know if Rainbow would be able to wake her up in the first place, but that was a step even further back than they'd anticipated.
"I can," Rainbow said with a fair amount of conviction. "It's physically- well, mentally possible for me to. I'm not sure if I would be able to, and bringing her back up from there is a whole other matter entirely. I do know I can't get to her while staying half awake, and I'm not going to be safe in there."