"Positive," she assures him. "You'll glow a little where it touched you, a day or two, but it'll do you no ill. People swim in it, Merlin knows why." Perhaps the most reassuring part of this will be how unconcerned she is at having stained her own hands with it, if he's inclined to be reassured by anything.

Upstairs, then; she points out the spare bedroom where she'll lay out clothes (her husband's, she's decided on his behalf that he won't mind) and shows him the guest bath. This, as the rest of the house, still has the pristine crisp air of newness and it's evident enough in subtleties that they haven't been long settled in.