I really didnt get the feeling that V was defending sai when P started accusing and screaming. He was defending his decision to do chowkidaari and acts all farz waadi by saying I will protect beti and beti ki aai. He got upset that his character was questioned even though he has admitted he loves Sai and has been pulling romeo like stunts. Its another matter that P deserves this- a cheating lying husband. But the way he presented the matter of Ajay Kamble, he said it in a way as if Sai was responsible which was completely unnecessary when he knows that P is going to spew crap anyway. He knows that Sai got involved because Kamble wife was her patient and she discovered domestic abuse due to that interaction as her doctor. And her recklessness in slapping Ajay also was prompted by Ajay's actions of trying to scare Sai which got her angry. yes she could have avoided it. but even if she hadnt slapped Ajay, she was still in potential danger just because she asked Varsha to file a complaint and Ajay Kamble knew that already. V knew that Sai was in potential danger even before slap - thats why he was trying to warn her. She was just being a good citizen asking a victim to report a crime and as a doctor supporting her patient who is being managed for injuries sustained from domestic abuse. So when he told the story he should have told the context also. He was laying the ground for P to latch on to how Sai is the irresponsible person who has put everyone in danger due to her actions. Its not like Sai not slapping Ajay would have avoided all problems.

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