Rufus was in charge of the bar, of course, and was more than happy to treat Robert to a proper bartender as part of his birthday present. And he's there, striped boating shirt and all, sneaking a cigarette off to the side before the party gets into full string.
He fully suspects it's going to be wild and crazy affair, and he'll see very little of Robert, social butterfly that he is. But it ought to be fun nonetheless.