The relative sizes of the characters change greatly between scenes. Grabovszky easily fits inside a glass bottle dropped from a plane by rats (who are the same size as the cat pilot in that scene), but when the rats fight Grabovszky they are almost his size. The cat hijackers on the plane are not much bigger than mice, even though in most scenes the cats are huge compared to mice. When Miguel drinks blood from a female cat, he's about her size, even though vampire bats are the size of a mouse in most scenes.