Tyrion: I must say I received a slighter warmer welcome on my last visit.
Robb: Any man of the Night's Watch is welcome at Winterfell.
Tyrion: Any man of the Night's Watch but not I, eh boy?
Robb: I'm not your boy, Lannister. I'm Lord of Winterfell while my father is away.
Tyrion: Then you might learn a Lord's courtesy.