Sirius trying to make up for missing Harry's childhood has started buying model trains and there is an entire floor of Grimmauld Place that is now miniature trains. Fleur is the only person that is both around (ie. Hermione and Ron are in dragged around by Molly) and good enough at charms to help him enchant whole rooms at a time. Have the two come closer together as they spend more and more time together as they both are using the time and subject matter to work through things.
Fleur might be trying to work out if she's actually interested in Bill or if it's his restraint that's fanning her flames (hence being around Harry who also has restrain is giving her perspective). Meanwhile Harry is both filling in holes in his magical education with Fleur and coming to terms that he's appreciated (and t