It's based on the catbus from the Japanese animated movie, My Neighbor Totoro
. It's anime, but not annoying Pokemon style- it's beautifully animated and a wonderful story of two little girls, sisters, in the 1950's whose mother is in the hospital for several months with TB. They move with their father to the Japan countryside to be closer to the hospital.
They discover that the forest around them is filled with mythical creatures, including Totoro:
The catbus is the creatures mode of transportation through the forest:
It is a wonderful movie- the director also did Spirited Away and Kiki's Delivery Service.