The gods have come down from Heaven, swearing off divine power in order to live side-by-side with humans. They form these groups called Familias, where a god assists a group of humans who've joined their familia. Most of them are there to help humans fight monsters in a strange sort of dungeon tower. Bell is the only human member of the Hestia Familia, a very modest group. It's clear that Hestia is very into Bell.