From MangaHelpers:

Makoto lives an ordinary life with his father and little sister, after the death of his mother. He spends his days doing the same things-- going to school, talking with his friends, hanging out with his girlfriend, and spending time with his family. One day, though, after he rescues a bird from an attacking crow, things take a very different turn. First, his girlfriend breaks up with him, and then, later that night, he's in a terrible traffic accident while running an errand.

He awakes in a strange place, with several people and the bird he saved earlier, which now appears to speak English. They explain that he is not yet quite dead, but not necessarily alive, either. The bird offers him a deal: If he works as their miracle deliveryman, he can earn back his life. As a miracle deliveryman, Makoto re-enters the world as a kind of ghost, providing people with letters or packages that give them just what they need in a difficult time. [tethysdust]