the tomorrow where I could apologize

Warning: there are un-marked spoilers!

Summary:

A group of six childhood friends drift apart after one of them, Meiko "Menma" Honma, dies in an accident. Over the years after the incident, the self-proclaimed leader of the group, Jinta Yadomi became a hikikomori, otherwise known as a "shut-in." One summer day, now ten years after the accident, an older looking Menma appears before Jinta asking to have her wish granted, but does not remember what it is. As a result, Jinta attempts to bring together his childhood friends in order to fufill Menma's wish.

jinta (jintan) yadomi

The basics:

As a child, Jinta was the de facto leader of the self-proclaimed Super Peace Busters. Jinta was energetic and outgoing during his childhood, but has become withdrawn and isolated due to the deaths of Meiko and his mother. After Meiko's death in an accident, the group of friends drifted apart, and Jinta eventually became a hikikomori, refusing to go to school and confining himself to his home. As a child, he was in love with Meiko but refused to admit it when asked. This started the chain of events that led to her accidental death. He believes that the Meiko that appears to him is not a ghost, but rather a manifestation of his stress, calling her "the beast of summer".

Nonetheless, Meiko's appearance encourages him to venture outside and reconnect with the members of the Super Peace Busters. He continually tries to grant Meiko's wish, but he becomes hesitant to grant it knowing that she will disappear if he does. He later does not want her to leave even wishing to marry her in her current state, but he decides it is time to move on and reconnect with his friends to truly send Meiko off. When she starts to disappear he takes her to the old clubhouse, so she can say goodbye to everyone but he loses his ability to see her, Meiko using her last bit of strength appears to all of them and they sadly say goodbye and say that they loved her. He later goes to school with Naruko, and stays connected with the Super Peace Busters.

From Wikipedia