Dead Dead Demons Dededede Destruction (ONA)

Three years ago, an enormous alien mothership appeared over Tokyo, and the possibility of the world's end became part of the city's everyday scenery. The government calls the newcomers Invaders and keeps developing weapons against them, while protest movements question both the war and the official story surrounding it.

In the middle of all this, Kadode Koyama and Ouran Nakagawa keep going to school, worrying about exams, friends, and the future as if the ship overhead were simply another building. Growing into adulthood forces them to see that the real threat is more complicated than an alien invasion, and that the humans claiming to protect the world may be just as capable of destroying it.