Comparing the leads in Japanese dramas, I've notice a commonalty, the girls are always perky, wacky and always getting into hilarious trouble. The archetype is very similar to the character Lucy Ricardo from the show "I Love Lucy". Generally though, the characters are not as intense as Lucy and they care a lot about the well being of others - a trait highly valued in Japan.
What I find interesting is that in real life, most girls are much more restrained. Not to say Japanese girls aren't perky and playful(they are) but if a girl in real life acted life those popular drama heroines, they'd be disliked for being too disruptive and troublesome.
Strange how there are disconnects between TV and the real world.
