Yuta Okkotsu has been haunted by his late childhood friend Rika for as long as he can remember. While she means him no harm, her vengeful spirit leaves a trail of violence and bloodshed whenever she protects him. That is why when he is captured by jujutsu sorcerers, the secret guardians of the world, he begs to be isolated to prevent anyone else from getting hurt. However, instead of keeping him from the world, his captors decide to teach him to control his powerful companion.