What is that sound

I wait as the lights fill the stage and this strange slurping sound start behind me.

I turn to see a young atractive guy on no more that 20 with his pants around his knees and a massive thobbing penis in his hand his eys are glazed I cant stop atching him although I know the show has started.

I feel strange aroused like the time I masturbated in the bath when I was 12.......................