Wife joke

There is a man who goes out drinking all the time and comes home very later every night. So one night his wife decides to teach him a lesson. She dresses up like Satan, and decides to hide in the dark, and scare him when he gets home. The man comes home, and his wife jumps out and screams in his face. He just looks at her and says, 'You don't scare me I am married to your sister!'