The Doctor drew breath to protest that it wasn't fair, realised that would make him sound like a twelve-year-old and shut his mouth with a snap.
"Well, demanding it back whilst waving a gun in his face didn't work, so goodness knows what will. Maybe I'll just have to say goodbye to it. But I - it's just the idea of seeing him walking around wearing it. And of Jack having to see him walk around wearing it!"