Yuta Okkotsu is haunted by the ghost of his childhood friend who died in a car accident. However, she is not the sweet girl she was before she died, but a monstrous and aggressive creature that the boy cannot control. So when Yuta is captured by magicians, the boy is glad that no one else will be harmed. Master Satoru Gojo, who detains him, convinces Yuta to enroll in a magic school so that he can learn how to control Rika and help people. However, Yuta soon discovers that evil spirits are not the most dangerous thing in the world.