Minerva's mouth twitched up in the crooked half smile that was the most her students usually saw of her somewhat dry sense of humor. "Yes well, the former tenant had a great deal of things he's not finished moving. As you can see," she answered. "Can I offer you some tea?" she asked politely, settling back into her chair herself.
She'd seen that brief, surprised expression on Tonks' face, and it was something McGonagall expected to see a great deal of in coming weeks. People were far too used to Albus in this office, her own presence was likely to be a shock, even when they expected it. It was to be expected, particularly when Minerva still had difficulty believing it herself. She understood the necessity, but she'd been content with her position and certainly hadn't envied Albus'. But here she was, and she'd do the best job she knew how. She wasn't Albus, but Minerva was well aware of her own talents, and confident in her ability to run the school. Of course it would be easier if Voldemort and his people left them alone, but she wasn't convinced that would be the case.
Politeness dispensed with - Minerva never was one to beat around the bush - she leaned forward on the desk, lips pursing for a moment. "The Aurors and the Order will likely want to have a presence at the school this year, I'd wager. As I cannot manage to run the school and teach my classes, I thought it might be best to kill two birds with one stone and offer you a position teaching here. Having a trained Auror handy can only help protect our students. The position of Transfiguration Professor is open, and you're more than qualified to teach, if you think you'd be interested?"