From the introduction:
Since the earliest days of space travel it has been one of Man’s fondest dreams to discover life beyond our Solar system – especially if that life is drop-dead gorgeous. Alien Angels is a game wherein that dream comes true, albeit in an unexpected manner.
Imagine a world much like the real world. People have the same struggles, natural disasters threaten many and political turmoil is rampant. Now add one extra ingredient; extraterrestrials are real. They walk the Earth in human guise, living and working alongside us, with no one knowing who and what they are. But this invasion differs from B-movie alien attacks in two important respects. One, these aliens have come not to conquer but to move in. No ships will fill the skies, and no death rays will incinerate all who oppose the newcomers from the stars. This war is one of quiet infiltration. Second, all of these invaders are young females. The reason for this provides the central conflict of the game.