Party needed to infiltrate a noblemen manor to assassinate him.
The barbarian has been reading a book on etiquette lately for whatever reason and convinces party he can get a job as a Butler.
The party decides to let him try. The lady of the house interviews him and just messing around I tell him to roll an "etiquette check"
He gracefully makes and serves tea and then suddenly pulls the table cloth out from under the tea set and didn't spill anything. The lady was impressed and hired him.
So it's time for the plan to go in action.
fighter infiltrated the mansion disguised as a guard and the other party members were currently sneaking into the kitchen to posion the food.
All the barbarian has to do was serve the food.
Then he noticed
The worst possible sin
nobles son was drinking his tea without sticking his pinky out.
The barbarian knocked the cup out of his hand and punched him in the face
Everyone freaked out and the party just improvised and rushed the noble to kill him and escaped out a window.
Even with perfect etiquette he couldn't mask the rage under his handlebar mustache