After Ciel's encounter with the werewolf in the forest, the "curse" breaks out: His body overheats, and his skin deforms. Sebastian rushes him to the Emerald Castle, where Sullivan performs a cleansing ritual. Ciel is submerged in a cauldron of herbal brew while Sullivan applies magical incantations to break the curse. During the ritual, Ciel relives traumatic memories of his childhood in captivity, which explain his current fear and disorientation. Despite being saved, Ciel temporarily loses his eyesight and reacts panically to adults – only Finnian is allowed to care for him.

Sullivan explains that the forest's miasma weakens the human mind and triggers the curse, transforming victims into beast-like creatures. In exchange for Ciel's healing, she demands Sebastian as a temporary butler, who henceforth organizes her tasks and instructs the villagers in daily chores. While Wolfram remains suspicious, Sullivan uses the opportunity to learn more about the outside world.

Meanwhile, Ciel struggles with the curse's aftermath: His blindness and psychological trauma isolate him, while the servants react helplessly. Sebastian analyzes the miasma and suspects supernatural causes behind the werewolf phenomenon.