Khushi just realizes that she is in love with Arnav. Her mind is still not sure whether he is the one. That's why her mind is doing the comparison. From her point of view there is heat and passion with Arnav but no appreciation, with Shyam it is sweet and mature and full of appreciation. She is still confused whether she can suit in Arnie's life or vise versa. Still La factor doesn't come to her mind.
When Khushi will see la and Arnav together she will know that that's not her place. And she doesn't have any good reason to deny snake's proposal. To get out fm arnav's life she will say yes to snake.
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