This song is a remix of a piano piece by Noriko Kose. The only reason why I know that is because Nujabes also used the same sample to make Reflection Eternal (another great song).

The piano with the driving bass and simple high hat + kick from the drum drives the song while the piano interlude continually plays in the background.  The piano gives a feeling of longing and ethereal beauty, while the bass and drums are bringing it back down to earth.

I guess for me it makes me think of yes, I miss you, but I can’t have you back. It’s been someone that I always have my thoughts in since there’s been so many times that I want to go back to the past or know that a relationship that I had can’t go back to where it was (whether it may be through mistakes made in the relationship, just naturally growing apart, or even through death). It just makes you want to appreciate every time that you have with a certain person, which makes it more of a reason why you should invest in people that you love and care for.