Why Kill Vinay - the blackkmailer

I was just thinking what was the purpose of vinay's appearance or the whole blackmailing issue with purvi as Vinay is now dead, the secret still remains and then...just stretching the story longer and longer and its getting more and more boring.

I truly hope that purvi confide in her mother about the truth if not anyone else. Onir alone cannot do it. Her mother if not arjun needs to know.