So Arnav wondered that what if Anjali asked Khushi to go with Shyam, she could have said no. But he didn't seem to realise how easily Shyam manipulated the mighty ASR using Nani to keep the raksha dhaga in his wallet.
He should have realised that Shyam can manipulate Nani and Anjali into conforming to what he wants other people to do.
Ek din batti jalegi! That's why they had the dialogue - Khushi na bol sakti thi Shyam ke saath jaane ko.
I wish they had made Arnav question Anjali that, why did they leave you alone to get the medicine and why didn't jijaji offer to stay with you when you were feeling dizzy. Why did he go with Khushi? To that Anjali could have replied - I wasn't comfortable letting Khushi go alone late in the night and made her go with Shyam. That would have been super!
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