The situation is clearly Riku's fault since he was a dickhead and didn't walk his sister home so he deserves to suffer just as much, if not more, than his sister. Now that I know the cause of Riku's problem, I have absolutely no sympathy for him, whatsoever. If his sister is still traumatized and suffering from the incident, then so, too, should Riku continue to suffer. If he had done what he was supposed to do, what he should have done as her older brother, then he would not be suffering now. He could have prevented the whole situation if he hadn't been such an obnoxious, selfish asshole.