Fukutarou Tamura is a human painter living in the Ashiaraiyashiki apartment building, a residence populated by various non-human entities, including demons and mythical creatures. He moved there following the "Great Summon" event over twenty years prior, an incident where an evil summoner triggered an invasion of devils and monsters that resulted in the loss of one-third of humanity.

His background involves navigating coexistence with his supernatural neighbors, leading to his frequent involvement in their conflicts and troubles. He is sociable, known for hosting gatherings like hot pot meals in his room where he interacts with peculiar friends, including individuals appearing as a cat-girl and a rabbit-girl. These interactions establish him as a central human figure fostering connections within the apartment's diverse community.

Fukutarou finds himself within a severe battle escalating in this supernatural setting, stemming from rising tensions among gods, devils, and the ruling entity "The Central." His role centers on navigating this volatile environment as a human resident caught in the midst of escalating confrontations.