He is about to launch into a vague, and probably partially incorrect explanation about bleach--the explanation of someone who has heard of it, read about its uses, and seen it in the grocers, but never had reason to use it himself--

But then she magics away the stains and he looks--well, certainly not baffled because cleaning with magic is nothing new to him (new as he is to this world)--but a bit touched and surprised to have been included in her efforts without exactly asking outright. She could have just done her own and left him to figure this out himself. Humans were ever surprising in their generosity, especially those who present themselves as brusque and grumpy. He admired his robes, then put a hand to his chest and gave her a warm smile.

"Thank you. That was very impressive."