Source from nokiirat and ANN
Tabe Mikako (the girl from Yamada Tarou Monogatari and Shikaotoko Aoniyoshi) will be Sawako. And Miura Haruma (the guy from that Gokusen season 3) will be Kazehaya. The movie will be in the theaters this fall.
I just don't know how to process my brian for how it would come in the live-action movie. Though if it was Miura Haruma, then I'm sure he would make a refeshing smile Kazehaya. I'm not sure about Tabe Mikako though. I hope the director of the movie focus on her nice traits and her smile rather than her scary features.
Who will play Ryuu? <--- I only concern for whether Ryuu being in the movie or not ><