That's Myrtle! This is the name of a flower, a ghost in Harry Potter, who lives in the ladies' room on the second floor. It was Harry, Hermione and Ron who made polyjuice potion's toilet. He died of the gaze of the basilisk, and stayed as a ghost because he was laughed at by his classmate Bain before he died. In the fourth part, Harry was helped to uncover the secret of the golden egg.