I think Sesha and Kabir will keep getting closer and then Seshivanya will find out Kabir's real identity. It'll be a awake up call for Sesha as to how far she'd gone down the rabbit hole.
Then maybe to prove a point to Shivanya as well as to her own self that Kabir is not her weakness and she's not in love with him, she'll kill him. And then deal with the angst n pain and realize she was actually in love with him.
But in later episodes it'll turn out that Kabir is not dead and it's in fact not so easy to kill off a supernatural shape shifter like Were mongoose.
Remember it's an Ekta's show. Dead is not dead here until the very last second of very last episode.