Yakumo Amagiri (雨霧八雲, Amagiri Yakumo), born Takehito Isegawa (伊勢川尊人 Isegawa Takehito), is the Artificial Island's resident rumored serial killer and known to its residents as the legend 'Killer Ghoul'.
He thinks at a much higher speed than most people (Gitarin describes this as him having a 'high clock rate'); thought processes that last several minutes for one person might last a few seconds for him. Time seems to 'slow down' for him as a result, and he is extremely deft at avoiding the blows of others. He is fairly acrobatic.
He is obsessed with the idea of normalcy, constantly reaffirming that he is 'normal' and that everything he does is not abnormal. He blames the nature of the Island as the reason he kills others.
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