mysid

Actually, I meant Peter's obliviousness to the staring boy sitting *next* to him, focusing instead on Snape who was, no doubt, not sitting anywhere near them (which is both funny, in this context, and a little sad in the larger context, when you think of how Sirius, Lily, and James are so busy looking for outside enemies later on that they don't notice the trouble coming from the friend right next to them), but I definitely think you're right that Peter would be oblivious to the true subtext behind Snape's (and Sirius's!) staring.
:-)
Em