Maybe Barun's character is a really dark one.
Maybe he had turned a bad boy, 'coz he had to fight for everyday means as a kid and an orphan, fending to meet his basic needs like food and shelter. Maybe he has turned a con-man who could fool you with his sophisticated language, mannerisms and behavior. Maybe he had to fight his way up the ladder changing colors like a chameleon, adapting to situations, carrying multiple fake-passports to fool tourists, investors, just anybody that could be conned to make tons of money.
All the while carrying his childhood scars, his hatred towards Chandni(the one and only person who he knew, for sure, was behind his parents' death and loss, everyone else was a unlcear, incomplete, blurry memory).
So an innocent happy kid, thrown out of the comfort of his family, home, friends, into the big wide bad world. He used his brain matter to get here by hook or crook.
And maybe he has been entering India on different aliases even before this time, trying to find the mystery of all the faces behind those vague memories. Maybe he was the one who kidnapped Chandni earlier to break her and get her talking about everything she knows, but before he could get anything out of her, she escaped.
#PEACE