• Hikaru Nakamura is in the top ten best-selling authors in Japan in the last ten years.
• The first time Nakamura's work has been made officially available in English.
• Affordable omnibus that collects volume 5 and 6 of the Japanese editions.
• The series has been adapted into an anime which available in the UK from MVM Films on DVD.
• The series was also adapted into a live action film in 2012.