モモ is a popular Japanese novel written by ミヒャエル・エンデ. The story follows a young girl named Momo who has the unique ability to listen to others. She lives in an abandoned amphitheater and helps her friends by providing them with comfort and understanding. The plot revolves around the mysterious 灰色の男たち, who steal time from people, causing them to become unhappy and disconnected. Momo embarks on a journey to confront these figures and restore the joy of time to her friends and the world. The novel explores themes of friendship, time, and the importance of listening.