The state of Aoihoshi (Blue sky) was once peaceful, glorious and people in Aoihoshi lives in peace and harmony under the ruling of King Tanaka Akiyoshi. However, Tanaka Minoru, brother of the King Akiyoshi wanted to upsurb the throne and decides to attack the ruler. Minoru massacred all the royal subjects and guards, including King Akiyoshi and his family (comprising of Queen Umi and Tanaka Ainosuke). Ever since, the state of Aoihoshi fell into the hands of KI