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Intro. Premise and Beginning (Episodes 1-3) The Infection: Brothers Utsutsu and Yume Hasegawa, who live alone after being abandoned by abusive parents, see mysterious red butterflies in a park. Yume is infected by a virus called "Pupa" . Transformation: Yume transforms into a hungry cannibal monster. Utsutsu, when trying to protect her, is also infected, but instead of becoming a monster, he gains extreme regeneration powers (similar to Wolverine). The Blood Cycle: To prevent Yume from devouring other people, Utsutsu decides to become her food, allowing her to eat parts of his body while he regenerates. Development and Flashbacks (Episodes 4-8) Maria and the Experiments: A mysterious researcher named Maria appears, monitoring the infection. She reveals that the Pupa virus transforms hosts into monsters with insatiable hunger. Abusive Past: Flashbacks show the brothers' traumatic childhood, the mother who considered Yume a demon since she was pregnant and tried to kill her

Pupa: the infected

@Ian David Tavares Dos Santos