Because he doesn't want to die! Not yet.

In the end, I still want him to be happy no matter what. I was willing to take all the blame for him and I did all those terrible things at our school just for us to be friends. And now we don't even talk anymore, and I probably won't be able to talk to him again because I'm dead and I deserve to die for everything I've done then and now and I--

[ huh, he didn't realize he's already crying till now ]