Clannad: After Story is without a doubt one of the greatest animes that I have seen. I never lost interest of it and I was always excited to see the next episode. The start was a bit slow but soon the series goes into a mucg higher level and because of that it becomes fantastic.
A 10 out of 10 is a worthy score to this anime and it is the first serie that I gave such a score. If you are looking for a anime that will make you drop tears then this is absolute a good choice.
I recommend it very much
