Ep. 12: Sebastian and Claude duel for Ciel's soul while Hannah manipulates the outcome for Alois.

Sebastian and Claude row to a remote island to duel for Ciel's soul, with Hannah holding his body. The demon sword battle ends in a stalemate until Sebastian splits the island. Ciel notes Alois's manipulation, leading Claude to realize Alois played him. Alois apologizes and fades, while Hannah reveals her contract with Alois required Claude's acknowledgment. She falls into the ocean with Ciel, urging Sebastian to dive in and kill him upon his awakening. Hannah reunites with Claude and Alois on the island. Later, Ciel awakens, sends farewell gifts, and leaves with Sebastian. Alois's wish caused Hannah to make Ciel's soul unattainable by rebirthing him as a demon. Sebastian remains bound to serve him. They walk through black and white roses toward a cliff. Ciel expresses gratitude, and Sebastian affirms his service to a fellow fiend. They jump together into the underworld.

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