Over two decades back, a malevolent summoner unleashed the catastrophic 'Great Summon', leading to the death of a third of humanity and the invasion of Earth by devils and monsters. Enter Tamura Fukutaro, a painter who relocates to the peculiar 'Ashiaraiyashiki' apartment complex, unwittingly entangled in the predicaments of his non-human cohabitants. Thus commences a fierce conflict embroiling gods, devils, and the enigmatic ruler known as 'The Central'.