It was painful to see Kaira, they both were hurting from bieng close yet far away. They were both afraid of loosing one another.
Naira was afraid to loose Karthik, she was afraid of his anger that his anger will take him away from her.
Karthik feared Naira being taken from him forever. The image of how she was so close to her still in his mind.
Personally I feel Karthik's fear was more, cause every time Kaira drift apart it is only for a small while and to become stronger than before. So even if Karthik didn't / doesn't talk to Naira in a few days they would still sort it out in the end, so Naira's fears even if it were to come true it won't have a horrible impact but Karthik he was going to loose the girl who is his everything and he could have lost her for her to never come back. It wasn't loosing her for a day or a week, it was forever.
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