Maybe it might happen like that. But so far what I see from Trishna's side is not love for RK. She is in awe of RK, Super Star. She needs him badly for her dreams of becoming a heroine.
And RK from his character he love challenges, so he might not go fora girl like Trishna, who will obviously fall for RK easily because she need him for her dream.
Of course Mukund is an outsider. So his role can be scrapped after sometime. But Trishna is lead's sister. So she is going to stay here for long and obviously will have an important role.
Personally I don't want third angle between sisters. For me it is disgusting. Sisters fighting for one man.
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