This is is a Japanese-language book or magazine devoted to fashion or cosplay ("COStume PLAY"), and may contain actual sewing patterns for creating your own clothing/costumes, as well as photos of completed outfits.
The title of this series is an accurate one -- while the girls photographed for the magazine are all beautiful, the intent is as much to show off hair, makeup, and fashions as much as the girls (they're all very young "junior idols") -- nothing racy. Profiles of the models are included as well. All text is in Japanese; 104 pages.