Rababou is a little star world creature forcibly sent by Higenoshita to aid Comet into finding the prince of the Tambourine Star World. He can easily detect twinkles with his tail and can inflate himself to fly, making him very useful for collecting star power. If he isn't exposed to the outside world, he is hiding in Comet's Twinkle Star.
Even though Rababou appeals to others as a cute little toy, he constantly nags Comet into staying on task, but Comet only believes that he should go out and have some more fun. Rababou may order his princess around a lot, but he truly cares for her as a friend and a princess. Rababou is one of the only people (well, in his case star world creature) that Comet can confide her feelings in. Later, Rababou falls in love with Spica's star world pet, Rabapyon.