Ep 13.5 or Another Epilogue episode:
In the BD/DVD-exclusive short "Another Epilogue", Otonashi remains in the school and becomes the new student council president, helping out other students to pass on.
The scene begins in a class showing students(NPC) starting on a test.
It then focus on a boy with blond hair and red eyes, he stands and makes a fuss about knowing that he died without achieving anything. He is shown talking about the point of taking the test, whether does taking the test and achieving a good grade means he will enter Heaven. Then he directs the question to the class, but of course them being mostly NPCs, no one answers.
Then the front door to the class opens and in walks in the Student Council President, it is no other than Otonashi himself. He walks up to the blond hair boy, grabs his collar and sternly questions him. Otonashi is shown telling the boy to quit whinning and do something about the problem. Asking the boy if he has something he wants done and what does the boy need to do to get what he wants.
Then Otonashi is seen referring to 3 of the SSS—Shinda Sekai Sensen (死んだ世界戦線?, lit. Afterlife War Front)'s members.
1. Iwasawa (岩沢?):
As seen in the line "One needed courage to face the past" and the next scene showing the cafeteria which the band Girls Dead Monster plays. This refers to Iwasawa since we know that she used music as an escape from her constantly fighting parents in life, but ended up dying from a brain injury she received. Once she faces the past, she manages to move on as seen in Episode 03.
From the line "Another person needed effort to make a dream come true." and the following scene showing the baseball field. This could either be a reference to both Yui and Hinata since Yui had regrets that ended up fulfilled finally in the baseball field as shown in Episode 10. As for Hinata, he was a former baseball player missed a fly ball in a similar baseball game in life as seen in Episode 04. Although it points to Yui more since she was the one who needed to make the most effort to have her dreams come true.
3. Yuri Nakamura (仲村 ゆり Nakamura Yuri?):
From the line "Yet another person needed time and friends." and the following scene that shows the principle's office and the former base of the Afterlife War Front. As we already know, Yuri vowed to fight against God after her three younger siblings were murdered by burglars looking for valuables when she was alive and never forgave herself for failing to prevent their deaths. But as shown in Episode 12, after destroying all the computer and denying herself of being "God" of this temporary place. She is shown in a scene where her siblings thank her for what she did. It seems through all the episodes, Yuri experiences a lot of things with the Afterlife Warfront and at the end cares for the Warfront just like she cared for her siblings. This answers the Time and Friends portion of what Otonashi referred to.
Otonashi is shown questioning the boy once again with the words "What about you?". The boy argues back saying that, right now, he needs the courage to stand up against Otonashi.
Otonashi is stunned for a moment and then smiles telling the boy that he can do it if the chooses to, and that he should know the way(to move on and disappear) now. Otonashi parts with the words "If you feel more anger at the unfairness of it all or lose your way, come to the Student Coucil room. I'll be there waiting" which simply means that, if you need anymore help, come and find me.
The scene ends with the NPC's chattering about Otonashi, who sits in the student council room with a vase of the flowers Kanade liked to grow, and the teacher is asking the class to quiet down, the boy is shown one final time crushing the test paper in his hands as the teacher tells him to sit down, And the Alternate ending finishes with the words "Next Stage" which gives out a possible continuation of the series.The End of the Alternate ending