The Cinder Twins and their Journey to Save the World.Hai no Futago wa Shirokuro Tsukezu ni Sekai wo Sukuimasu.; 灰の双子は白黒つけずに世界を救います。; The Cinder Twins will Save the World without Black or White.; The Cinder Twins and Their Journey to Save the World.; 立于黑白之外的灰之双子拯救世界.

14 years have passed since the "White Hero's" and the "Black Demon King's" decisive conflict during the "Black and White War". The world, now lacking of a Hero, was domineered by self-proclaimed "Heroes" who were showing off their power. However, some mysterious twins turn the tables around with their wisdom and ability...!