Hedonismbot's mouth and eyes keep changing throughout the film. His mouth is either shown with just one row of teeth or one row of teeth and two lines creating a "mouth" like Bender. Also his pupils change from being round to being square like most robots.
When Fry and Colleen are lying in bed, post-coitus, his hand is around her shoulder but it is the same colour of Colleen's skin. (And not his own flesh tone - it vaguely looks as if she has three hands.)