Near the end of the movie, Kitano tells Noriko to shoot him. She fails to do so, so Kitano starts to shoot. Shuya ends up killing him before anything happens to Noriko. Noriko wouldn't have died anyway, because Kitano's gun was filled with water... He never meant to hurt Noriko in any way. Also doubles as a Tear Jerker.
In the Manga, any moment between Mimura and Yutaka. To say Mimura has the patience of a saint is a huge understatement.
Among the biggest ones being when Shinji accidentally kills one of their classmates. Yutaka snaps, calling him out on it and damn near losing his trust in Shinji. In the end end, however, he decides to forgive Shinji and stick with him, due to how patient Shinji had been with him, despite all of his screw-ups. This display of faith was enough to bring Shinji to tears. Sadly, this is almost immediately followed by Yutaka's death, which came completely out of nowhere.