The scene was heartbreaking. He wants to keep it together and be strong for her, but the guilt is killing him. He doesn't have anyone to confide in and wants handle it all on his own. The only problem is the burden is too much for him to handle so he went back to the only thing that gives him relief. He can't cope with reality and wants to escape. It nice to see her protect him and confront the ACP. Its good now that she suspects his motives. Hopefully she won't let him manipulate her any further.
The ACP's anger and lack of morality makes sense now. He wants justice by any means necessary. I think he assumed that they went on with their lives as if nothing happened. The reality is completely different. Om was addicted to drugs and now is heading down that dark path again. Prinku suffers from panic attacks and severe anxiety...it's so bad she can barely speak. The incident seems to have harden the ACP as well. He probably feels like he didn't enough either to protect his sister and the guilt is killing him too. We see the consequences of what happened that night and how it changed their lives, but I really want to know what actually happened. I think what all three of them think happened might be completely different from what actually happened that night. I'm really enjoying the ACP/Om/Prinku track. The more the story delves into what happened the more interesting it gets.
The brother -sister scene was acted and filmed beautifully. Kudos to the actors and the crew.