"Mom and dad thought that Karlsson was one of those pretend friends that children get when they feel lonely. That's why they bought a dog for Little Brother. Of course Little Brother loves his Bimbo, but Karlsson is an even better playmate. "I want fun , otherwise I'm not me," says Karlsson, when he comes flying in through Little Brother's window, alert and enjoying himself and always ready for new adventures.The second book about Karlsson on the roof, in which Miss Bock, the headmistress whom Karlsson loves to "irritate", appears for the first time."