Rudiger is "the little vampire". One evening he flies through the window of Anton Bayers and a friendship begins although there is some distance at the beginning. Rudiger makes an adventurous, wild impression. Although it is strictly forbidden for vampires to inform humans about their existence, Rudiger meets regularly on Saturday evening with Anton and opens him the way-of-life of the vampires. He also makes it possible for him, to fly like vampire using a real vampire cape. But because Anton's parents want to get to know him absolutely, Rudiger has to disguise as a human and appear for tea, where his contact to humans is being discovered and he is banned from the vault by the vampires. He moves into the cellar of his friend, where he vegetates in a very poor way (without cape and hungry because of that) which is obvious for everybody visiting him. He is very crotchety and discouraged until he has a cape again and may also visit the Everything-is-forgiven-Party. When shortly after that the vampires have to leave because the graveyard is destroyed, he also is very sad because they also have to leave his good friend Anton, although he does not often show his real feelings.