Pupa

Utsutsu and Yume Hasegawa, siblings who've grown up together, find themselves struggling with abandonment and abuse. Their lives become complicated when beautiful red butterflies start appearing, seemingly drawing them into a dark reality. A mysterious virus called Pupa is spreading, causing its victims to undergo a grotesque physical transformation. Utsutsu is only partially affected, gaining regenerative abilities, while Yume is completely changed, her desire for human flesh becoming uncontainable.