The phrase comes from Tokyo Ghoul, the manga by Sui Ishida that began in 2011 and its 2014 anime adaptation. Protagonist Ken Kaneki becomes a half-ghoul after an organ transplant and spends the story hiding that nature from humans. His admission in Japanese became a quotable moment among fans, circulating in AMVs, edits and soundboards well beyond the original scene. Its continued use reflects how central Kaneki's split identity remains to the series and to anime meme culture.