In a land where humans and monsters destroy each other, a young boy searches for the key to peace. Written and illustrated by Mitsutani, this dark fantasy shonen manga presents a world ravaged by war and mistrust, where the line between human and monster is often blurred. The narrative centers on a young boy who, after a tragic event, embarks on a perilous journey that forces him to confront the deepest prejudices of his world and the mysterious nature of his own identity.

The main character is a noble's son who was raised by his father to hate monsters, in stark contrast to his mother, who loved and cared for supernatural creatures before she vanished when he was young. This internal conflict between his upbringing and his mother's compassion becomes the story's driving force. The inciting incident occurs one night when the boy witnesses a mysterious wolf monster, named Alfur, stealing his mother's corpse. This frightening encounter triggers a monstrous transformation within the boy's own body. To uncover the truth about himself and to retrieve his mother's body from the wolf monster, he leaves his home and sets out on a journey to find the eight monsters scattered around the world.

The setting is a harsh fantasy realm where conflict is the norm. The narrative structure follows the boy's quest as he chases Alfur across the land. While the official VIZ Media synopsis highlights the general search for peace, more detailed plot summaries reveal a personal and visceral motivation: the recovery of his mother's remains from the creature that stole them. This journey brings him face-to-face with various monsters, challenging his preconceived notions as he learns that these creatures are not simply evil, but often feel like lost people trapped in a cycle of violence. He is guided by a spirit's tale of a forgotten era when humans and monsters lived together in harmony.

The creator, Mitsutani, was only 20 years old when the series began, and it marks his first serialized manga. The story is known for its textured and dreamlike art style, which creates a moody and emotional atmosphere that has drawn comparisons to classic fantasy works. The series is structured as a complete narrative with a defined ending, serialized in Weekly Shonen Sunday before concluding with a total of 36 chapters collected across four volumes.