I'm unable to connect with Kabir. Hence, I can't get attached to his character.
Regarding your theory I will go either with the first or maybe the last. In yesterday's episode Mannu's aunt says he resembles Arjun so he might be related to him in some or the other way. So, him being connected to Manoj is not possible. The second thing is I don't think he's an NRI but him being involved in illegal activities and that too with Manoj doesn't seem possible. And, I feel his look too might be deceptive. He might be an IAS or IPS who's working undercover to catch these goons.
Yesterday when Mannu said he resembles her Angel papa he didn't look surprised so, maybe he might be related to Arjun.
I hope your last theory comes true.
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