The tunnel is dangerous, and they must keep the High Priest in check. It is for that reason the trio need reinforcements; they need another Graduate.

No happy tales remain within the castle’s forsaken ruins. The danger is unimaginable: Yayoi and Keitaro risk their doom, prepared as they may be.

None who have encountered the castle spirit survived to tell the tale, but both the living and the dead should fear the High Priest; it is not salvation he prays…