Lillipup is a small quadrupedal mammalian Pokémon that resembles a Yorkshire terrier puppy. Its body is covered in tan and brown colored fur. Its face is covered by a scruffy mass of long tan fur. It has pointed ears, large black eyes, and and a red nose. It has stubby limbs with three toes on each foot. It has a patch of blackish fur on its back, and a short brown tail.
Though it's adorable, lively and gentle, it's still smart enough to have the choice to decide whether it should leave its trainer and how to battle or socialize.
Lillipup was seen in episode 15 of Pokémon Best Wishes under the control off Gym Leader Lenora. It was very friendly and playful, as it jumped into Iris' arms then ran over to Ash to play, but when the battle started, it took out Tepig with one Take Down.
In the games, the first Gym Leader has a Lillipup, whereas in the anime, the Gym Leaders only have Pansage, Pansear, and Panpour.
Lillipup appears to be based on a Yorkshire Terrier puppy.
Lillipup's name is derived from "Lilliputian" and "puppy". The mythical land of Lilliput, as described in Johnathan Swift's novel, "Gulliver's Travels" is where a race of little people called Lilliputians live. This could relate to the small size of Lillipup.