the best thing about showers/bathrooms is theyll usually have a windoiw that opens, tiled walls and hard floors- no carpets or fabric curtains which means there isn't really much the smoke can "soak" into (so to speak).
hence why its very easy to clear the smell out of a bathroom, the bonus of a shower and using smelly lotions and potions nicely covers up what smell is in the air

Jonny