Taisetsu na Koto wa Subete Kimi ga Oshiete Kureta aka I Learned All the Important Things from You aka the Japanese drama with the longest title ever is the story of two teachers and one of their students. Basically:
Natsumi Uemura and Shuji Kashiwagi, work at the same high school and are planning to marry in six months time. Natsumi (played by Toda Erika) is confident and leads Shuji (Miura Haruma), who is less confident in his abilities. The morning of the school year's opening ceremony, Shuji awakens to find Hikari Saeki (Takei Emi) in his bed - an issue as he is engaged; a crime as she is his new student.
But, it's so much more than that. Taisetsu is a human drama; a melodrama even. None of these three characters are innocent in any of the drama that unfolds during the first five episodes. Each has issues they need to work out - Shuji is following along with everyone; Natsumi is too used to the normal stuff; Saeki has some mental issues springing from illness and guilt - and these issues lead to their problems. It's a true human drama, in that the story lines are all about the difficult decisions the characters make in the few months following the incident of Saeki and Shuji waking up together.
Now, on to some spoiler-ish character thoughts.
Natsumi - She's bright, strong, and well loved by her students. She's a kind woman, and she tries very hard to help long-time boyfriend/fiancee happy. She leads Shuji, because she always had. I love her voice overs, as they speak the truth. In episode 4 or 5, she comments that Shuji is becoming stronger because he's caring about/loving someone for the first time - its just not her. What makes me feel for Natsumi is that she is falling in love with Shuji all over again - because he is getting stronger and more confident - but, he's slowly slipping away from her. And, did I mention she's pregnant with his child?
Shuji - Oh, dude. He cannot make up his mind. He truly is in a love triangle. He loves Natsumi, because he always has. She's kind, she helps him, and she's beautiful. He loves her, but at the same time he's pulled toward Saeki. He's seeking her out and going toward Saeki time and time again, when Natsumi is waiting for him. Shuji is wishy-washy. It's insane, because he seems to deeply care for both ladies and both are teaching him how to grow up and be a better person.
Saeki - is a damaged young lady. The first three episodes play with her being the villain of the piece, and then episode 4 happens. Shuji and Natsumi's relationship would have fallen apart if she hadn't come along, but she is still a major part of the reason for it falling apart so soon. And, when you learn the hows and whys of what happened - you can't help but feel terrible for Saeki. Especially, after she tells them she'll forget everything and that she'll move on. And then, Shuji keeps going toward her. Girl feels guilty and hurt and she's still in love with her favorite teacher, Shuji.
Honestly, I think all three of these characters are teaching each other the important things. All three are growing because of the other two. What's really interesting to me is that the two female leads are way more complicated and interesting than the male lead. I really love that. It's a slow drama, and certainly isn't for everyone. But, if you like the actors, melodrama, slow build-up romances, or complex and real love triangles, then this drama is for you.