Wait crap, I just saw movie. My favorite Japanese movie is Tori Girl, with an INCREDIBLE female lead (v strong). Its not eeeexaaaaactly a romcom, its more comedy than romance, but Tsuchiya Tao's and Mamiya Shotaro's chemistry is through the ROOF!
Ahh it's hilarious! The interactions between Tsuchiya Tao and Mamiya Shotaro is probably my favorite thing in the entire thing in the movie. And also, now that I think about it, their characters are probably my favorite couple in ALL the dramas/movies I've watched. Shit. Never have I ever thought of a drama couple being PERFECT for each other without psycho-analysing why they are perfect for each other.
