Odd Film (spoilers)
Most of the film was a rather nicely portrayed, understated, love story.
Then they bolted on an ambiguous and unpleasant ending which didn't make a great deal of sense.
It's almost as if they missed out a part of the story.
I'm not sure the ending was "bolted on". Certain events earlier in the film could be attributed to the evil brother. The vandalised car and the harassment by Brother's fellow gangsters all pointed towards his final act of murder. Also, the scene where he explains his bad character to Ton could be seen as a sort of pre-murder confession. The confession thus making the crime in his eyes inevitable and therefore justifiable. So there were pointers earlier in the film to the brutal ending.
One could speculate on Brother's motives: jealousy of his "good" sister finding happiness when he could not?
I think my toaster is in with the machines!