Since its formation as a girl group in 2005, AKB48 has become a phenomenal success and institution in Japan. Having originally recruited fans with photocopied fliers and daily performances in the Akihabara area of Tokyo, AKB48 now saturates Japan. Its members--nearly 800 of them, including five sister groups and four so-called "rival groups" across Japan, as well as six sister groups in other Asian cities--appear in print, broadcast, online, and...