Aap ek baar bol do ki aap mujse pyar nahin karte..

This was what Nakku told him when she confronted him with the Suresh fiasco...

Aap ek baar bol do ki aap mujse pyar nahin karte..Phir mein chali jayegi...

I guess when Seema comes in - Nakku thinks either his first love is better for him , to heal all the wounds that has been inflicted upon him , and may try to leave him, for his goodness - or may be some circum stances will let her think that he doesnt love her , when Seema comes in...

Dunno ...some random thots....

And that should trigger Dutta , to break his shell and confess whats plainly written on his face and engraved in his heart - He belongs only to Nakusha - and no one else...