Coprophagia is the eating of feces or dung. The sexual paraphilia involving a sexual arousal from the eating of or sight of eating someone eating feces is called coprophilia.
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The practice of eating feces, whether human or otherwise, is something that is typically classified as unsafe for human health. There is a small population of individuals who partake in the practice. The Human Centipede is a film example of the sexual interest of eating feces. This practice can be harmful to human health.