I have come to understand that there is no "why" in Japanese pop art - or Japanese scientific pursuits, for that matter. There is only "can." Which is why I am firmly convinced that if a Giant Robot Apocalypse is at hand, it will be courtesy of our Pacific neighbors.
Looking at these, they seem harmless enough. "Magical Girl" is an anime/manga genre, after all, and that's all this looks like to me. I have no doubt that there are creepy middle-aged Japanese dudes slavering over this, just as there are some slavering over every other depiction of too-young girls already developing curves, but that's to be expected, and is another story entirely. The pictures themselves aren't creepy.
Really, after a lifetime involved with this stuff, this barely rates a 2 on the Weird From Japan Meter (which, when evolved into a higher state, goes up to 100, not 10). Give me a call when Bayonetta and Vampire Hunter D get stuck in a live action La Blue Girl sequel made with all robot actors.