Frith didn't try argue that she had to stay awake too but instead would comment upon her second statement, that they had to stay awake to see what happened in the moonlight. Hopefully it was a clear night, the sky certainly hadn't been all that cloudy upon entering the cave, surely they wouldn't have cruelly appeared out of nowhere to hide the moonlight and ruin any chances of them finding out tonight what would happen.
The light slowly streamed in though, certainly not as bright as the light that the sun had provided and it meant that the result with the crystals wasn't all that strong either. It was fainter, and to be honest whilst still pretty was an environment that she could easily see herself falling asleep in if they stayed much longer. It was a night-light variation, a subtle glow though not enough to truly captivate their attention as the sunlight had.
She would be reluctant to move all the same, it was nice sat here with Frith and she simply had to resist that temptation to lie down beside him again. As she felt her first yawn coming on however, Novella got the feeling that perhaps it would be best to call it a night before either gave into temptation and they fell asleep here. "Shall we head back now before either of us falls asleep?" She would question, though her lack of movement certainly suggested that although the idea was hers, she was still reluctant to actually act upon it.