"Oh, but you aren't someone random, ma'am." he says, keeping up his slightly fake smile. Looking her over, debating what to actually do now that he is here. He begins to consider that this may have been a bad idea, however he is here and must make the best of it. He takes a quick look at the masked monster before turning his face back to Susan quickly.
His body language definitely shows he is a bit uncomfortable being around the masked man, and likewise there is a sort of tenseness directed at Susan. While his feet do remain planted in place, he is obviously having a little trouble figuring out what exactly to do with his hands at the moment.
"C'mon ma'am, can't I show a little concern?" he tacks on at the end.