Wouldn't you like to shut him the fuck up?
The Laugher is tall and slender. He has pale skin and dark hair and eyes. He also has an large mouth and often sports a Cheshire Cat grin or is just laughing like a mad man.
The party first hears of The Laugher from Kethra when they free her. They then encounter him in the keep at Castle Bromont. He flees before the party can even get close to him.