Looks like PaRappa was in such a rush to get to school on time that he forgot to put on his pants, and now he's paying the price. What makes matters worse, he grabbed a pair of tighty-whities from his underwear drawer (he tends to wear whatever he grabs from there). Bet he wishes he were wearing his lucky dog bone boxers right now!
PaRappa the Rapper and its characters are the intellecual properties of Rodney Alan Greenblat and Sony Computer Entertainment.