Nina is one of the main characters in Monster. She’s a blond and charming young woman, who lives her normal life as a student. Her life quickly shifts when she finds out that she has amnesia. She doesn’t remember her real identity. Nor does she remember that she has a twin brother, who tries to contact her so that they can be together. She finds out that her name is actually Anna, and also about her brother’s murders. After she meets doctor Tenma she begins to help him stop Johan.