Klaus is usually seen with a lollipop. Him and Bibi have known each other ever since they were kids. But when Hana asks if he is Bibi's friend, his reaction is pretty much appalled. Klaus is a little younger and lower in rank than Bibi which is the reason why he doesn't refer to himself as Bibi's friend. Klaus despises how Bibi, even when young, effortlessly takes the things that other people (him) want and then tossing it away like it was nothing. That makes him believe that Bibi cares about nothing other than himself, but he is soon proven wrong when Bibi comes to save Hana in his little experiment.