Pupa

The "life-and-death sibling" story follows Utsutsu and Yume Hasegawa, a boy and his little sister who find themselves all alone. One day, Yume sees a mysterious red butterfly and her body undergoes a strange metamorphosis—into a creature that eats humans. Utsutsu struggles to find a way to restore his sister. <br><br> (Source: Anime News Network)

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