Board Thread:Questions and Answers/@comment-2016820-20130417213851/@comment-691135-20130417225539

If you say Shinken Red, who are you referring to - Takeru or Kaoru? This is where the Princess designation is used - to distinguish Takeru from Kaoru. In-show, she is called Princess because the Shiba clan is royalty. In-show evidence trumps everything else therefore Princess Shinken Red is the correct designation.