Why ASR did not defend himself yesterday

Now why did he not call off Khushi's bluff? Was it because he did not want La to get another earful from Nani? No. He seems to be willing to take the blame for the sake of protecting Khushi since it is Khushi who shifted the blame to him. If he were to deny that he did not do it, it would make Khushi a liar in front of his family. Nani has a good impression of Khushi which will suffer a beating if she comes to know that Khushi is repeatedly protecting La and that too by resorting to lies. He knows that Nani cannot tolerate lies. So he would rather admit to a mistake he did not make for Khushi's sake rather than see her reputation suffer by telling the truth. True that La's mistake will also come to light by his denial but then La has nothing to lose further, for Nani does not have a good impression of her anyways. So I feel it is Khushi's reputation he was protecting and not La's.