Six childhood friends grew apart in high school. One of them is Jintan, now a shut-in. He gets a request to fulfill a wish for Menma, the only one of their friends to have stayed the same over the years. In order to grant her wish, he will have to find and reunite their old friends.
This was the only anime that has made me bawl out crying in my entire life. Seriously the plot may be a bit out there but as the anime progresses and they characterize the chars, you fall in love. By the end you'll be crying like a baby and say why?! but you understand it was needed for the series, and the realization that you have to come back to reality. Highly recommend to anyone, except with people who don't have a heart.