First: Fabulous. I like this glimpse of the James-Sirius relationship as well as the first signs of James-Lily learning to work together as a couple. Even if they aren't a couple yet. (These last three have been so so good. I'm looking forward to the rest!)

One tiny Brit pick: The "They would so all do me" was somewhat jarring -- "They would so all shag me" might be better.