On the boundless sea, there is a ship floating. It is so huge that it can hold millions of people. Its whole body is connected with blue and white, exuding a charming light like gold. It raises six dazzling white sails on the ship. Engraved with four shining golden characters: "Wandering School". What does that mean? Yes, this is the legendary high-end school that can only be seen when you are still in school - and the story I am telling you is about to happen on this ship.