Brilliant. I love Mrs. Button and her wonderful insights, especially her practical notes on elopements. And Argus is perfectly IC as 'caretaker' par excellence. Of course he's the head of the hearth, at Hogwarts. And he makes a great husband. Not sure about the aspic in the tomato thing, though. A normal Gazpacho might be tastier.
The way he gets Snape to postpone their divorce is utterly believable. What a wonderfully cosy night they must have had, Snape with his books, and Argus with his darning.