Bippy is a monkey that A.J. brought to Dimmsdale Elementary School when he thought it was "Monkey Monday", although it turned out to really be Muffin Monday. Bippy appears to enjoy muffins, bananas, and especially banana nut muffins. Timmy Turner seems to be familiar with him, as he knows Bippy by name.
Bippy looks like an ordinary monkey with brown fur and blue eyes. After his world changing wish, Bippy also wears the same clothes and pink hat as Timmy Turner.