When the show's focus was on Ehsan's feelings for Katha I had some thoughts in my mind about it.
Ehsan had told Viaan quite a couple of times that he was pretty serious about Katha and wanted to start a relationship with her but Viaan always thought Ehsan just wants to do time pass/indulge in a fling with her and then dump her just like he had done with his previous girlfriends. Since the beginning he never trusted Ehsan's words whenever he talked about Katha only because of his previous flings. Not once did he think that what if Ehsan has actually fallen for Katha. I mean he never thought that if Katha could change his own views and opinions about women then maybe she must have changed Ehsan too. Even on holi when Ehsan was high on bhaang he was talking about Katha and again Viaan didn't pay attention to that. I found that pretty weird of Viaan, I mean this not trusting his friend's words about his feelings for Katha.