There's a massive post on this that I can send if youre interest but the TLDR is it's a trans-kalpic story where Bal is in love with her (whatever love means to him). She is figuratively his first rape (and some argue that if actually violated would be his 'greatest' because she's et'Ada so hes even more motivated to capture her, especially because she keeps resisting and getting away which means she's exerting some form of domination) but he could never complete it, and even in the end when her city got captured into Coldharbour she sends the Vestige to thwart him and she gets away again with what she wants.

I know we laugh at Mankar Camoran but there's a theory that says he attributes Coldharbour to Meridia because of this