Harry is a one-time character of Rugrats, in the episode Reptar on Ice. He is presumably the manager and supervisor of the show, and also served as Leo (the actor playing Reptar)'s boss. Harry also served as the opening emcee for the show, announcing its' introduction. While Harry was very enthusiastic about the show, Leo wasn't really enjoying his job, though Harry didn't seem to mind. He is voiced by Michael Bell.
You can find Harry gallery here.