Ah! My Goddess is about Morisato Keiichi, a 21-year old student, and the goddess Belldandy.
One night Keiichi tries to order Ramen, but he calls the Goddess Relief Office instead. Belldandy steps out of his mirror and says that she will grant him one wish. Keiichi's really short, and he thinks that's why he's single. So he wishes to be with someone like her forever. Belldandy misunderstands him - she thinks he wants to be with her forever! She grants his wish.
The story evolves from there, introducing other inhuman beings (goddesses, demons and peoples like that), but basically everything revolves around the love that Keiichi and Belldandy have for each other. ^_^
