Philip is the secondary villain in The Curse of the Were Rabbit. He is Victor Quartermaine's pet Bull Terrier dog and a rival to Gromit.
Philip is smarter than he looks as he saw Gromit as a worthy opponent and was a skilled fighter against him.
While Victor hunted down the Were-Rabbit (which turns out to be Wallace), Gromit and Philip fought each other. In the end, Philip mistakenly bit his own master trapped in the fake Were-Rabbit costume while the villagers chased him away. According to Twilight Sparkle's official journal, he and Victor were killed during a shoot out in Tokyo.
He and Victor were never mentioned in Pinkie Pie's alternate biography. However, he and Victor were briefly mentioned in Applejack's second alternate biography.