While maybe this belongs in music more, one thing I found interesting is the rumor about that Japanese idol/music culture is very segegrated. Meaning Female Pop Idols does not do collab with male pop idols. How true is that statement.
Here is a few korean examples from way back, this is kind of related since if an AKB48 member does something like a collab with some well off pop group, she could get in trouble.
http://www.youtube.com/watch?v=gV4Qi...eature=related
http://www.youtube.com/watch?v=_YM2F...eature=related