Over two decades ago, an evil summoner unleashed the catastrophic event known as the "Great Summon". As a result, one third of humanity perished and the Earth was overrun by devils and monsters. Tamura Fukutaro, a painter, unwittingly becomes entangled in the drama of his non-human neighbors when he moves into the "Ashiaraiyashiki" apartment complex. This marks the start of a fierce war between gods, devils, and their ruler "The Central".