It pains him that neither of them seems to know what to do with this situation, how to broach the new boundaries of their relationship -- the new definition of their relationship. The both of them are nervous; he doesn't have to try very hard to see that in Watson, and he doesn't have to try hard to read his thoughts, either. He feels certain enough to reply to Watson's thoughts, though in a less... typically-him way.

"It's good to be home," he says softly, his eyes on Watson. "I've missed you."

It's certainly true, and it's a bit of a relief to say it, since he can't yet say what he would really like to (I love you, please don't shut yourself off forever from me).