The Testament of Sister New Devil, Volume 8 (The Testament of Sister New Devil #31-35.5)

Everything's on the line - Basara and his allies charge headlong into battle against their deadliest enemies yet. Zest brings her full might to bear against them, but even she pales in comparison to the threat waiting in the wings: The dread demon Zolgia! Against a foe so strong, has Basara met his match? He'll need everything in his arsenal to make it out of this one alive!