Very nice. I love those little moments that can be plausibly inserted into the canon timeline and help round out other characters -- things Harry would not have known or seen. I love it even more when it's Snape we get to explore. Although his thoughts are understandably melancholy, I couldn't help but smile a bit at the whole getting out of here without any witnesses thing. Sorry, Snape, but Harry will be there. (Which only leads on to their next adventure, of course.)