Awesome!Sirius! (: I love how this is the rare occasion where he would rather kiss Snape than kill him.^^). The angst of the pairing is also particularly palpable - with the absence of Snape-homicidal!Sirius, James takes on the role as he gives in to the urge to hit Snape. I don't know why, but I seem to have come away with this "island" feeling for Snape, even though you pointed out that he is not particularly alone, and Slytherins approach and speak to him.