In Doumori, an imbalance of spiritual forces threatens to plunge the small city into complete chaos. Thankfully, for the students of Doumori Elementary School, new teacher and exorcist Meisuke "Nube" Nueno is determined to prevent the malignant spirits—known as youkai—from accomplishing their evil deeds.

The first student who catches Nube's attention is transfer student Hiroshi Tateno, who displays inexplicable outbursts of anger, often lashing out at his classmates. When they find out that Hiroshi is possessed by a youkai, Nube manages to free his student thanks to the demonic power sealed in his left hand. However, a youkai hiding behind the appearance of doctor Kyousuke Tamano bursts onto the scene and quickly abducts Hiroshi.

Helped by his student Kyouko Inaba and his expertise in the occult, Nube quickly uncovers Kyousuke's sinister plans. Rushing to Hiroshi's rescue, Nube will show once more that he will stop at nothing to protect his beloved students against all supernatural threats.