The Doctor's smile was a little forced, but he hoped nobody would notice. "It's July, is it?" he said. "Didn't know that. TARDIS didn't say. Alright, it's summer cleaning."

She was offering to help. Well, it wouldn't hurt to accept the offer, would it? The fact he accepted didn't mean he had to be around to see her promise fulfilled...

"Thanks," the Doctor said, "help would be great. I promise not to do any of the above to you," he said, still smiling. "Loki has no reason to worry. But I have to say, it's nice to see him so worried about you."

He gave her a lopsided grin. Just wait until the end of the barbecue, Doctor. Then you can leave and continue as you did before, as you always have. The wanderer without a home.