[He lifts a hand to rub at his shoulder, awkwardly, because he knows he should have gone to them first thing in the morning and pretended that's when he arrived, that would have been easier.
(Also to answer your question, because you'll disapprove of what he did and worse, be disappointed in him, and he can't handle that.)]
Sorry, I- I knew you were teaching, I didn't just want to barge in, so I came here instead. I thought I'd come to the house later, when you'd all be there. [Never mind he's already been there, and met Emma. Well. Maybe she won't tell you that.]