Susan glances at Lancelot, surprised by that note, especially given that he knows she's never cared for this particular arrangement. She offers him her mug, in case he might like a sip of tea, and says, "He was taking advantage of your goodwill. You ought to be able to talk about your day with your friends." This is putting her concerns very lightly, of course, but there's a queer look to his face that she can't quite parse.