|From left to right: Skuld, Belldandy, and Urd
Ah! My Goddess is a manga series created by Kosuke Fujishima. With the first chapter published in 1988, it is one of the archetypal harem series. The plot focuses on a college student named Keiichi Morisato who accidentally places a phone call to the "Goddess Help Line" and nervously wishes for the goddess Belldandy to stay by his side forever. Eventually her two sisters move in, and a bunch of crazy stuff starts happening. It is notable that Belldandy and Keiichi have one of the slowest romances ever, after 250 manga chapters and 21 years of publication, they have not even kissed yet.
Standing in the Battledome
The series is loosely based on Norse mythology, the 3 main goddesses being versions of the Norns (Belldandy is a translated version of the original name, Verdandi). It also uses a digital cosmology system, where the universe is controlled by a computer known as Yggdrasil (the Norse world tree) and errors in this system can cause fluctuations in reality. The best feats are universe-level, although it should be noted that there are many dimensions and universes in the series. As for the powers of the individual characters, they are shown to be very versatile, but have definite limits, and often by inconvenienced by the same things that would inconvenience a normal human. A first-class goddess supposedly has enough power to destroy the earth, but this has never been demonstrated.
There have been several anime adaptations, but, as is usually the case with anime made after the manga, they are non-canon.
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