Since childhood, Tomoki Sakurai has been waking up in tears due to his dream of an angel. Sohara Mitsuki, his friend, is worried and turns to Eishirou Sugata, an odd sky enthusiast, for assistance. Eishirou concludes that Tomoki's dream is connected to the perplexing floating object named the New World, which has eluded scientists. To investigate the sky's enigma, Eishirou recruits members for the New World Discovery Club and convenes a meeting. Tomoki's life drastically changes, however, when a mysterious girl drops from the sky and names him her master. Sora no Otoshimono documents the daily exploits of the New World Discovery Club as they uncover more about Angeloids who have descended to Earth.