One thing I will say about Japan that bothers the hell out of me is how centered it is on middle- and high-school in terms of media. There almost seems to be an obsession with youth. I like the humor in a lot of Japanese dramas but the majority of them being set in high-school gets really tiresome. Korean dramas, on the other hand, are often about working professionals, sometimes even with characters in their thirties. It's refreshing, to be honest.
It's the same with games, with so many main characters being high-school age. There is nothing like playing a game with a cool, bad-ass character, then learning later that he's like 15--and that girl with long legs and huge breasts is supposed to be 14. Contrast that with western games, where characters are usually older and more experienced.
There is nothing wrong with it, exactly, but sometimes it does get kind of annoying.
