Leo, you're a real killjoy. Come on, why don't you make up with your friends? Leo Lausemaus may be a little mouse, but he's just like all the other little children in the world. That's how Leo likes to win every game. It is not easy to understand that this does not work and that sometimes his friends are even a bit better at it than he is. Where it leads to, when such a louse is just angry about it, this story tells us with beautiful illustrations and loving texts.