Player A - I attempt to chat up the barmaid.
GM - Ok, roll for it... You suceed. Player B?
Player B - I recognise Player A's behaviour as being heretical and see that he has being tainted by the Ruinous Power of Lust and Excess. I execute him in the Emperor's name.
GM - Ok, Player A, you're out of the game, and the bar is now on fire. Oh, and the barmaid has no head anymore.