Having looked through all Risako's blog photos and as a photographer, I honestly can't see that her pictures are different from any other random instagrammer. The "dreamy style" you reference is just a simple -10 or -20 Saturation. Also the focus is terrible, but if she's using a phone to take them then that's understandable. There's a girl in AKB who has a real camera and real photographic knowledge, called Takeuchi Miyu. Her G+ has some good examples of her work, mostly landscapes. Her self-portraits do suck as well though.