It was very easy to see how it would end, but that didn't make it any less enjoyable!
I was just mentioning in the IRC that there's really nothing original about this, the enjoyment is more about how well it's executed. Like listening to someone perform an old standard, you know the content already but it's still worth your time for the performance. In this case, I like the airy quality of the art, it reminds me of Konno Kita's stuff.
As to the actual story, it's basically a mix of Graffiti, as others have mentioned, and The Cherry Tree Correspondence. The story of the latter was pretty obvious too, but I still liked it.