
The day before he begins attending high school, Ashiya Hanae becomes possessed by a strange fuzzy yokai. Being possessed causes him to fall ill, and while spending the start of his high school life repeatedly making trips to the nurse's office, he comes across the contact information of the Mononokean, which specializes in exorcising yokai, and decides to call them. When Ashiya finally visits the Mononokean, he meets the morose master Abeno Haruitsuki.
The day before he begins attending high school, Ashiya Hanae becomes possessed by a strange fuzzy yokai. Being possessed causes him to fall ill, and while spending the start of his high school life repeatedly making trips to the nurse's office, he comes across the contact information of the Mononokean, which specializes in exorcising yokai, and decides to call them. When Ashiya finally visits the Mononokean, he meets the morose master Abeno Haruitsuki.

When Ashiya begins working part time at the Mononokean, the master Abeno impresses upon him that he should pretend not to see any yokai other than the Mononokean's clients. However, the kind-hearted Ashiya is unable to keep his word, and the yokai won't leave him alone. Based on their surprising strength and numbers, Abeno believes there must be a powerful demon serving as their leader.