In 2004's Ninja Gaiden, Rachel is a fiend hunter whom the protagonist Ryu Hayabusa meets in the Holy Vigoor Empire, where she is on a mission to destroy the fiends, as well as find her missing sister, Alma, who has become a Greater Fiend.
Rachel made her first fighting game appearance in Dead or Alive 5 Ultimate/Dead or Alive 5 Last Round [REF].