Jinrui wa Suitai Shimashita has streamed the 3rd promo trailer. The anime will begin to air on July 1st.
ANN’s synsopsis of the anime is the following:
“The story is set several centuries into the slow decline of mankind. Earth has now become the realm of “fairies” — 10-centimeter-tall (about 4-inch-tall) creatures with remarkable intelligence. The human protagonist of the story serves an important duty as the international arbitrator between the fairies and humans, and she returns to her former hometown of Kusunoki. She chose this job because she thought it was an easy job she can do, even when she is as old as her grandfather. However, she learns that her job is anything but simple when she meets the fairies.”
You can view the promo trailer by clicking the video available over at ANN.