3.69 out of 5 from 23 votes
Keiichi Morisato is a shy student who serves as an errand boy for his roommates. One day he tries to order some food, but accidentally dials the goddess help line instead! A goddess named Belldandy arrives and tells him she will grant him any wish, but only one wish. He doesn't take her seriously, thinking his roommates are playing some kind of prank on him, and decides to play along and call their bluff. Being unpopular with the girls, he wishes to have someone like Belldandy stay with him... forever! Much to his surprise, Keiichi's wish is granted and Belldandy herself will stay with him forever; and that's where the trouble begins. Women aren't allowed in the dorm, and the magical force that granted the wish won't allow them to be separated. As if things couldn't get worse, Belldandy's sisters begin to show up as well!
Ah! My Goddess and Mamotte Shugogetten are almost a reflection of each other, in both plot and characters.
While Ah! My Goddess follows the antics of an older male with a sudden girlfriend (in this case the Goddess Bell-Dandy), Shao follows a similar plot only involving a high schooler. Both follow the attempts of the protagonist to get used to the increasingly strange and odd occurrences that come from having a paranormal creature living with them, while their new girlfriends struggle to adapt, conform, and remain "normal" to stay with the boy the fell in on.
While not every plot point is identical, they both feature the romantic rivals in each direction, coming to terms with their feelings for one another, and the general light-hearted content of both series'.