Kuro is a young armadillo who, due to a prophecy passed down for generations among the people of his hometown, is destined to be sacrificed when he turns sixteen. When he panics and runs away from home shortly before the scheduled date, the townspeople's lives are thrown into turmoil as they begin to call their own beliefs into question, while Kuro himself must struggle with both his own doubts and the dangers of the wilderness. Despite starring animals as its main characters, this short novel touches upon decidedly human themes such as mortality, the importance of friends and family, and the extent to which the common good can override one individual's freedom.