"You were trying to get home? You left a scene of a crime, you could be hurt, you come to ask me about a mole, and you're going home?" Simon didn't believe it; perhaps he should, but it seemed a little strange, very strange.
He looked at the approaching man and thin woman. What was it about them that made him think they were very odd? Well, it could be simply that the other guy wouldn't go away. Simon wanted to be the good guy here; not that the other guy had said he would be. The good doctor decided that crossing his arms and giving the mole woman a good stern look might get an answer out of her that made sense.