"You sneaked up on me." That didn't happen often. It was nearly unprecedented. Maybe he really was out of it. Or more likely he was just so used to her presence that she could sneak up on him. He liked that explanation better, even if he did think it was probably closer to the former.
"I'm sorry, I didn't mean to... talk to myself behind your back." Anakin blushed and looked away. He would have to make a note to shut his door when he talked to himself in the future. Or just not talk to himself, that would probably solve the problem too. "Um. Come in."