Grey didn't know when he fell asleep, but he did.
In fact, he was so tired that despite the fact he had given Amunet the crown specifically to sense the changes to her Frame, he knocked out before he could even experience that. His mind was just too overloaded, his body had gone through too much, and he didn't have the bandwidth left to do much of anything else but sleep.
And much like usual, his mask naturally flowed onto his face.
On the one hand, this was probably some form of protection for him. On the other, it was certainly a protection for those around him as well, because his snores could have probably leveled small hills at this point.
Whatever changes the Mechanical Jaw Lineage had made to his body, they were certainly still there during his sleep, and the feeling of getting real rest for the first time in a long while really let everything within him reset down to his very cells themselves.
