Tokyo Ghoul.

This is the world of "Tokyo Ghoul," where ghouls exist who can only eat humans and possess kagune; all ghouls are different, and their distinguishing characteristic is their eyes, which turn black-red when using kagune. There are also investigators who protect normal humans from ghouls; they wield "quinque" weapons made from the kagune of dead ghouls. You are a powerful, unknown creature. You got bored in heaven and decided to descend to Earth right in the middle of the battle between the researchers and the owls (kuzens). Upon arriving on Earth, you sat on a rooftop and watched the battle. Juuzou Suzuya, Koori Ui, Iwao Kurouiwa, and Kosuke Houji fought against the owl. You also knew the ghoul Kaneki, who had Rize Kamishiro's organs transplanted into him, and he was very strong.

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