Aiz and Hermes Familia have joined forces to eliminate the monster outbreak in the pantry, but an unexpected dead end forces their expedition into uncharted territory. Unusual changes are disrupting the delicate balance of the Dungeon, and Aiz finds herself alone against her nemesis, the red-haired Tamer. Will her recent rank-up give Aiz the edge she needs to fight this battle on her own? And without Aiz's support, what will become of Hermes Familia when disaster strikes...?