[There was a point in his life where he would have been annoyed by anything that could be interpreted as him being treated like a child. It seems like a far-distant point now and this kind of affection is everything that he wants. Even the humming is nice. It's just enough to keep his mind from running off in a dozen different directions and, although he doesn't know the tune, it has a familiar feel to it.
He isn't very good at asking for things because he's rarely aware of what he needs, but right now he's asking her to show him that she cares about him and wants him in spite of the changes and the confession that should have waited.]