Kasumi is a central character in the 'Dead or Alive' series, known for her role as a skilled kunoichi and a member of the prestigious Mugen Tenshin clan. She is a runaway ninja who left her clan to avenge her brother Hayate, violating the laws of her clan and becoming a target as a result. Kasumi is characterized by her exceptional speed and agility in combat, as well as her determination and sense of justice. Her storyline revolves around themes of loyalty, betrayal, and the pursuit of truth.