The girl who he had saved from getting bullied found him after school and decided to walk home with him.
He didn't really want her to walk with him, he got so used to distancing himself from people. But he wanted to be nice and let her walk with him.
And you talk a lot, don't you?
You don't talk much do you?
I don't have friends, and I'd like it to stay that way.
Oh, well I thought that maybe we can be friends.
After the small conversation they had they both went home.
At night is when he really shows his emotions. When no one is around. Because he's afraid of being seen as weak. He was crying, because he pushed someone away who could actually be his friend. He didn't have a friend ever since his parent's died. He was alone.