From the introduction:
"Magical World is a campaign setting quite unlike any other. There were a lot of sources of inspiration that ultimately led to its creation, but it began with watching Sailor Moon and wishing for Usagi's bumbling to have real consequences now and then, for an end to the Monster-of-the-Week syndrome, for enemies who were smart and vicious enough to attack before the magical girls could finish posing and shouting, and for magical attacks that actually hurt and have consequences in the real world. There are plenty of other magical girl shows out there; Pretty Sammy, especially the TV series, is a favorite for its character development, sweeping plot, and, just as importantly, the fact that it mercilessly pokes fun at the genre.
"But I still watched Sailor Moon regularly, until it went into reruns. Why? The Sailor Senshi are a bunch of girls who fight an endless array of monsters. They stand up to and overcome every challenge that comes their way, not because they're super-perfect comic book heroes (though it seems that way sometimes), but because they're brave and willing to risk everything for what they believe in. If those aren't admirable traits, I don't know what would be.
"Magical World is what came out of this paradoxical perspective on magical girls. It puts them into a world of high stakes and dire consequences where, as in the real world, power can be used selfishly as surely as it can be used to help others. Some hate them, some worship them, some ignore them, and a few hunt them down. It is a place where magical girls and their youma foes are ubiquitous, and a world that truly both loves and hates them. Whatever you feel about magical girls, it can happen here.
"Magical girls come in countless varieties; saccharine heroines, servants of darkness, hired killers, idol singers, vigilantes and more. They can save the world or bring it damnation. The choice is yours. Strap in, have your henshin wand handy, and get ready for a bumpy ride."
Magical World used "rules modules" to adapt the setting to different systems. More were planned, but were never written.