You seem pretty updated with all the latest season j-dramas, but you don't even know abt this old japanese film that dates back 7 years ago?

Boku wa Imouto ni Koi wo Suru aka
My Sister, My Love was a film originally released back in 2007 by Hiroshi Ando, and since movie productions are usually filmed about a year in advance for productions that are not complicated in nature or involves sfx, that would prob mean Nana Eikura filmed this when she was still 18-19 yrs of age and Matsumoto Jun in his early 20s.
Being ard 19 y/o and involved in mainly high school period dramas/films are just about right for almost any modern popular joyuu/actress found these days, just feel free to take a look at the active actresses that are greatly involved in latest japanese TVCMs and dramas found on our screens these days, for example people such as
Kasumi Arimura and
Haruna Kawaguchi are just a couple of them to quote an example.
Well just saying.