Escorted by the elven knight Shiran, Majima Takahiro and Lily arrive at a fortress within the monster-filled forest. There, they meet members of the first expeditionary force and Takahiro's best friend Mikihiko. Not everything is as it seems, however. As the two of them begin to learn more about this world and its inhabitants, they must closely guard their secrets from all those around them.

Meanwhile, Gerbera, Rose, and Katou Mana remain hidden in the forest. They continue to keep a watchful eye on the fortress, but an unexpected event befalls them...