*Episode summaries are not guaranteed to be spoiler-free*
There exists a town called Guri. There, the haibane, people with grey wings, live along with normal humans. They're not humans because they have wings and halos. However, they aren't angels either. No one knows who they are really. They just live there.
1: Dream of Falling from the Sky
4: The Clock Tower
5: The Abandoned Factory
10: Haibane of the Abandoned Factory
11: Darkness of the Heart
12: Passover Festival