Oskar listens to
Kvar i min bil while going through his scrapbook and hums it to himself after the bullies stuff his pants in the urinal. I think it's become more than just a song to him, it's also the dark side of himself that he keeps hidden from everyone else, except Eli. When Eli tells him she's
"The same as you", Oskar knows he's finally found someone he can share his secret with.
Försonade is a love song about someone asking forgiveness and pledging their love. I don't think it's a coincidence that Eli is the one who plays this. She wants to be with Oskar but doesn't know if he'll accept her for what she is or what she's done. He does.
The songs remind me a little of the Rubik's Cube because they can all represent characters trying to reach out to someone else. I don't know if that was their intention but it works out that way.