What is the name of the song in Koukou kyoushi?

 Lily_B:

I'm currently watching the drama Koukou kyoushi (http://mydramalist.com/japanese-drama/790/kou-kou-kyoushi-2003). I like the ending song, so I was wondering, what's the name of that song?

Edit: I found it, eventually. If anyone cares, it's a song by Morita Douji called Bokutachi no shippai:

http://youtu.be/IXYxnJLcjMM

It's late, but I know that fortunately you're still active here, let me share another song from my beloved and favorite singer, Douji Morita: Tatoeba Bokuga Shindara (Assuming I will die). As you can see, in some sense, the song is used in the short movie: 'Ao to Shiro de Mizuiro'

https://youtu.be/DMFLoiOXdtE

The original song start at around 00:40

As for Bokutachi no shippai, it's not exactly OST, if you mean an original song. Morita sang it in 1976 (she ended her short career in 1983), but maybe she re-sang it for this drama.