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.
I've been feeling worse and worse 
since this thing showed up,
Seit dieses Ding aufgetaucht ist,
fühle ich mich immer dreckiger.
Me siento cada vez peor
desde que esta cosa apareció.
Mon état ne fait qu’empirer
depuis qu’il me colle,
Me sinto cada vez pior desde
 que essa coisa apareceu.