According to the official site for the anime adaptation of pupa, the anime series will premiere this fall. It was previously announced at Anime Contents Expo 2013 in March that the anime was already in the works.
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.