Now we know that Neeraj is a split personality and the 2nd being takes over and he now wants to kill Saloni because she wants to take Neeraj to the psychiatrist & cure him so the 2nd personality will never ever exist. Bittoo now takes over and tells Saloni how his father had killed his mother for money(The 1st scene is shown in the flash) Bittoo is the same boy.All the murders were a revenge of those who had sexually molested his mother and himself in the past.