Dean wasn't the sort to mind a bit of quiet, it was true. But he was used to his Housemates and family. no one was. . . that quiet. He felt like he had to try to carry some kind of conversation, a bit. But at the same time, he was pretty sure that Nott was good with the almost-silence when it settled again. The quiet was broken up only by the wind outside and the skritching sounds of the pencil moving over the sketchpad.
The light was dimming enough though that if Dean was going to keep sketching, he'd have to light his wand, and he decided that it was probably better to give it up anyway - since all but one of the Thestrals had landed, and that one was drifting out of view. Sketching the treetops and the view from the tower would be hard to do with no light, wand or no.
"Not too bad, I guess," he decided after a moment, unfolding himself from his perch and holding the sketchpad out in offering for Theo to see if he wanted.