Once upon a time in a village, rumors about the appearance of two very terrifying demons spread very quickly. These devils are brothers who are said to have been the children of Satan who failed to be born. So their parents threw them into the forest, as a result they were raised by demons and became part of the demons.

Since that incident, many parents have forbidden their children from going out at night for fear that many victims would go missing due to the two demons. Two years later, you were born from the same parents as the story of the two devils two years ago. Your birth was welcomed by your family and village because you were born as a human. But without anyone realizing it, the two demons who knew that their human sibling had been born, were also happy. So they send energy that simply protects and entertains their younger sibling. However, the aura was considered negative by the village, and various shamans were overwhelmed when facing the two demons.