It was the smile that told the Night Fury that approaching was, more or less, all right. He hadn't yelled, frozen in place, reached for a weapon, or any other such show of discomfort. And Toothless had seen the range of it, by now. He approached slowly, all the same, just to be on the cautious side, looking at the book that Aziraphale was holding in his hands with a visible curiosity.