It's true, Sans does. As if he's napping at his desk or station back home, restful and unshadowed by nightmares or job stress. It's comforting to see, after the last several days and the anguished expression earlier.

"...Yeah, I think this worked out okay. But I wonder... Did she leave to go pay attention to something else?"

Papyrus looks around the area they're in for signs that anything new and terribly wrong is about to happen, or signs of continued yelling and clashing and exploding in the distance. After everything that's gone on, he's lost track of what the plan at this point is.