It is rude to smoke in someone's home.
Jeremy is over at his friend Nick's house when he feels a craving for nicotine.
Jeremy wants to smoke a cigarette.
Jeremy tells Nick he has to go outside to have a cigarette.
Jeremy lights up a cigarette in his friend Nick's house.
Nick will think Jeremy is considerate of his house and space.
Nick will kick Jeremy out of his house and tell him he smells.