Suuran Digit

Soyogi Academy is a private school whose social order is defined by the nine noble "Suuke" families—the Number Families—who hold privileged rank above their peers and carry a secret with them: the Suuransen, the Number War. This ancient periodical conflict determines the rankings among the Suuke and selects the Soyogi who leads them all. The war was believed finished when one of the numbers broke away and the conditions for it could no longer be met. Then "the number that should not exist" reappeared, and the ten numbers are assembling again. A carved seal is guiding those involved toward the field of battle. Her name is Reisaki Hiroka. She signals the beginning and the end.