Humanity Has Declined

The heroine begins her job as a mediator and finds it not to be what she expected. Whilst observing an abandoned site, she encounters a group of fairies and brings some of them home with her. After getting over their initial worries, the heroine finds the fairies to be quite talkative and curious. She gives them some names, only to be tasked with naming all the other fairies as well. Finding the abandoned site turned into a metropolis overnight, she gives the fairy population a naming dictionary so they can decide on their own names. The next day, the heroine finds herself hailed as a god and ends up causing chaos when she tries to pass the responsibility onto someone else, leading to the city's destruction. (Source: AniDB)