Little Mugu on the Paggy Throne

This book tells the story of a boy who lives in a land ruled by a king. One day, a braggart arrives in this land. He possesses the ability to catch other people's thoughts with his wild hair and thus guess them. When the king was once a little tired of ruling, he held a lottery; the winner would be allowed to rule his kingdom temporarily. The little boy Mugu won the prize and ruled the land, turning many things upside down. He even had to wage a war, which he did in a very unusual way. Perhaps in the end there were even two kings, one young and one old. I can't quite remember, so I can only recommend that you simply search for the answer yourself in the stories of this book.