The night of the crimson full moon. The full moon of Konichi, who had been living a normal high school life, is caught up in the battle to become the only magician in the world at the school where he returned to get his forgotten. It is explained that this world was overflowing with magic from the girl and the new moon which met there, and it is a full moon which runs away puzzled.

As dawn breaks, Mangetsu awakens in Shingetsu's apartment. On her way back home, Shingetsu tells her more about mages and GRANBELM. Determining that Mangetsu has no intention of fighting, Shingetsu prepares to erase her memories, but her technique is unsuccessful. When Shingetsu is about to give up, Mangetsu asks her for more information about GRANBELM.

Mangetsu meets Anna at school in a chance encounter, and Anna tells her that Shingetsu ruined her family. During lunch the next day, Mangetsu tells Shingetsu that she wants to participate in GRANBELM. Shingetsu offers to help her, but at that moment, a car carrying Anna and some of her family passes by

GRANBELM is finally down to two participants. Their mechs surpass their own limits, but eventually they can no longer withstand the impact sustained during the battle, and their functions begin to fail. When Shingetsu's situation grows dire, she's surprised by the appearance of Mangetsu, who was supposed to have disappeared...