He is an entertainer for the Shark Club. However, he is terrible at it, as all his jokes are unfunny. The crowd will insult him for such bad humour. Luckily, he has a fence surrounding him, for protection against items that might be thrown at him.
If the Chosen One is accompanied by Myron, the comedian will start making jokes about him.
The following is based on Fallout 2 cut content and has not been confirmed by canon sources.
The Chosen One can actually substitute him for some acts, after talking to the casino pit boss and telling him that the comedian is weak. The pit boss will then say "Yeah, he stinks worse than brahmin shit", and ask the Chosen to do an act. If the Chosen One has enough Charisma and does well, they will be invited to do another act within a week. The reward for each act is 150 XP.
Females on the other hand, could dance if their Charisma was equally good, but also required a good Agility for the act. A ball gag could also be used for this purpose.
End of information based on Fallout 2 cut content.