Arguments in Grimmauld Place

Canon with Novus Ordinem Voldemort. (I'm not egotistical enough to call it a 'verse.) Written to help address NOV's divergences from canon. Harry, Ron, and Hermione are hiding out in Grimmauld Place after Voldemort attacks the Wedding in Deathly Hallows. They get a visit not only from Lupin, as in canon, but also from Sirius.