Percival is described as the creator of the drink PEP; however, in his first appearance, he is shown to have an unnamed, mentioned son. Doofus Drake felt enraged for hiring a grown-up to play his son to which Percival fearfully regrets on hiring his real son in his car.
Role in the series
Percival P. Peppington first appeared in the Season 2 episode, Happy Birthday, Doofus Drake!".
When Goldie takes Louie to the carnival at the tree house doing a con artist plan, Percival attends Doofus Drake's birthday party where Doofus blames him for hiring a grown-up actor pretending to be his son and demands him to hire a child actor to pretend to be his son. Just as Percival prepares to get his real son in his car, Doofus presses a switch that causes him to fall into a storage of honeybees, much to Doofus being unhappy for many liars in his party.
In "Louie's Eleven!", Percival can be seen briefly kicked out of the museum for supposedly attempting to crash the party. He later leaves in anger.
- His design appears to based on that of Gene Wilder's portrayal of Willy Wonka in the 1971 musical fantasy film, Willy Wonka & the Chocolate Factory, especially the cartoony depiction of him in the Wonka candy commercials and the design of Willy Wonka in the Wonka candy brand (now Nestlé Candy Shop).