I haven't read the story in a very long while, all I remember is that that woman was crossdressing as a man in one of the MC's missions, they traveled together for a long while, and formed a bond. I don't recall him saving her when she was a child, or anything like that?
Either way -- from her perspective, she got to know a man to his best and worst of his qualities as they traveled together, and fell for whatever she saw in him.
But from his perspective, some random rich, young girl suddenly started hitting on him out of nowhere, for no apparent reason (being "tipped off" by the "guy he traveled with" is not a good enough reason)
WTF was he supposed to say? Why is the story treating her courtship as if it's only natural "he has to give in"? Why must he "accept her feelings", and why she can't accept the reality THAT HE'S NOT INTO HER?
The entire situation is fucking weird and unnatural.